IPAC2022 - List of Keywords (vacuum)

Paper	Title	Other Keywords	Page
MOPOST006	Beam Commissioning and Optimisation in the CERN Proton Synchrotron After the Upgrade of the LHC Injectors	MMI, proton, operation, synchrotron	54
	A. Huschauer, M.R. Coly, D.G. Cotte, H. Damerau, M. Delrieux, J.-C. Dumont, Y. Dutheil, S.E.R. Easton, M.A. Fraser, O. Hans, G.I. Imesch, S. Joly, A. Lasheen, C.L. Lombard, R. Maillet, B. Mikulec, J.-M. Nonglaton, S. Sainz Perez, B. Salvant, R. Suykerbuyk, F. Tecker, R. Valera Teruel CERN, Meyrin, Switzerland
	The CERN LHC injector chain underwent a major upgrade during the Long Shutdown 2 (LS2) in the framework of the LHC Injectors Upgrade (LIU) project. After 2 years of installation work, the Proton Synchrotron (PS) was restarted in 2021 with the goal to achieve pre-LS2 beam quality by the end of 2021. This contribution details the main beam commissioning milestones, encountered difficulties and lessons learned. The status of the fixed-target and LHC beams will be given and improvements in terms of performance, controls and tools described.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST006
About •	Received ※ 01 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 02 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST011	CEA Contribution to the PIP-II Linear Accelerator	cryomodule, cavity, SRF, linac	74
	N. Bazin, J. Belorgey, S. Berry, J. Drant, O. Napoly, A. Raut, P. Sahuquet, C. Simon CEA-DRF-IRFU, France S. Arsenyev, Q. Bertrand, P. Brédy, E. Cenni, C. Cloué, R. Cubizolles, H. Jenhani, S. Ladegaillerie, A. Le Baut, A. Moreau, O. Piquet CEA-IRFU, Gif-sur-Yvette, France O. Napoly Fermilab, Batavia, Illinois, USA
	The Proton Improvement Plan II (PIP-II) that will be installed at Fermilab is the first U.S. accelerator project that will have significant contributions from international partners. CEA joined the international collaboration in 2018, and will deliver 10 low-beta cryomodules as In-Kind Contribution to the PIP-II project, with cavities supplied by LASA-INFN and power couplers and tuning systems supplied by Fermilab. This paper presents the CEA scope of work that includes the design, manufacturing, assembly and tests of the cryomodules and the upgrade of the existing infrastructures to the PIP-II requirements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST011
About •	Received ※ 13 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST014	The 325 MHz FAIR pLinac Ladder RFQ - Final Assembly for Commissioning	rfq, linac, proton, coupling	82
	M. Schuett, U. Ratzinger IAP, Frankfurt am Main, Germany C.M. Kleffner, K. Knie GSI, Darmstadt, Germany
	Based on the positive results of the unmodulated 325 MHz Ladder-RFQ prototype from 2013 to 2016, we developed and designed a modulated 3.4 m Ladder-RFQ. The Ladder-RFQ features a very constant voltage along the axis as well as low dipole modes. The unmodulated prototype accepted 3 times the operating power of which is needed in operation* corresponding to a Kilpatrick factor of 3.1 with a pulse length of 200 µs. The 325 MHz RFQ is designed to accelerate protons from 95 keV to 3.0 MeV according to the design parameters of the proton linac within the FAIR project**. This particular high frequency for a 4-ROD-RFQ creates difficulties, which triggered the development of a Ladder-RFQ with its high symmetry. The results of the unmodulated prototype have shown, that the Ladder-RFQ is very well suited for that frequency. For the applied cooling concept, the Ladder-RFQ can be driven up to a duty factor of 10%. Manufacturing has been completed in September 2018. The final flatness & frequency tuning as well as the final assembly have been completed. We present the final RF measurements and assembly steps getting the Ladder-RFQ ready for shipment and high power RF test prior to assembly. Journal of Physics: Conf. Series 874 (2017) 012048 Proceedings of LINAC2016, East Lansing, TUPLR053 *Proceedings of LINAC20118, pp.787-789
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST014
About •	Received ※ 12 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST022	Upgrade of the Radio Frequency Quadrupole of the ReAccelerator at NSCL/FRIB	rfq, operation, MMI, RF-structure	104
	A.S. Plastun, J. Brandon, A.I. Henriques, S.H. Kim, D.G. Morris, S. Nash, P.N. Ostroumov, A.C.C. Villari, Q. Zhao, S. Zhao FRIB, East Lansing, Michigan, USA D.B. Crisp, D.P. Sanderson NSCL, East Lansing, Michigan, USA
	Funding: Work supported by the National Science Foundation under grant PHY15-65546 The ReA-RFQ is a four-rod room-temperature structure aimed to be the first step acceleration of rare isotopes as well as stable beams before injection into the ReA SRF linac. The beams of charge to mass ratios of 1/5 to 1/2 from the Electron Beam Ion Trap at 12 keV/u should be accelerated to at least 500 keV/u to be efficiently accelerated in the main SRF linac. Since the commissioning of the original ReA RFQ in 2010 the design voltage has never been reached, and CW operation was never achieved due to cooling issues. In 2016 a new design including trapezoidal modulation was proposed, which permitted achieving increased reliability, and would allow reaching the original required specifications. The proposed new rods were built and installed in 2019 and commissioned in the same year. Since then, the RFQ has been working very successfully. Recently it was opened for inspection and verification of its internal status. No damage and discoloration were observed. This contribution will describe the RFQ rebuild process, involving specific RF protections and other technical aspects related to the assembly of the structure. Results of the operation with a variety of beams will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST022
About •	Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 11 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST049	Electron Cloud Build-Up for the Arc Sextupole Sections of the FCC-ee	electron, collider, simulation, sextupole	191
	J.E. Rocha Muñoz, G.H.I. Maury Cuna Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Mexico K.B. Cantún-Ávila UADY, Mérida, Yucatán, Mexico F. Zimmermann CERN, Meyrin, Switzerland
	Funding: Consejo Nacional de Ciencia y Tecnología (CONACyT) - México In particle accelerators that operate with positrons, an electron cloud may occur due to several mechanisms. This work reports preliminary studies on electron cloud build-up for the arc sextupole sections of the positron ring of the FCCe⁺e⁻ using the code PyECLOUD. We compute the electron cloud evolution while varying strategic parameters and consider three simulation scenarios. We report the values of the central density just before the bunch passage, which is related to the single-bunch instability threshold and the electron density threshold for the three scenarios. In addition, we compare the simulated electron distribution across the central circular cross-section for a chamber with and without winglets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST049
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT018	Advancing to a GHz Transition Radiation Monitor for Longitudinal Charge Distribution Measurements	radiation, target, simulation, electron	267
	S. Klaproth, A. Penirschke THM, Friedberg, Germany H. De Gersem TEMF, TU Darmstadt, Darmstadt, Germany T. Reichert, R. Singh GSI, Darmstadt, Germany
	Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract no. 05P21RORB2. Joint Project 05P2021 - R&D Accelerator (DIAGNOSE) In the past, longitudinal beam profiles have been measured with e.g., Feschenko monitors, Fast Faraday Cups (FFC)* and field monitors. Feschenko monitors usually examine an average shape over several pulses and FFCs are interceptive devices by design. In this work we want to present the progress in the development of a novel GHz diffraction radiation monitor which shall be able to measure the longitudinal charge distribution of single bunches within Hadron beam LINACS non-destructively. A proof-of-concept measurement has been performed at GSI. We aim for a resolution of 50 to 100ps at beam energies of β=0.05 to 0.74. electronic field simulations were performed using CST Particle Studio to determine an optimal RF-Window, which also suits as vacuum chamber and the beam energy and angular dependencies of the diffraction radiation for different materials were analyzed. * A. V. Feschenko (2001): Methods and Instrumentation for Bunch Shape Measurements. In Proc. PAC’01, paper ROAB002 ** G. Zhu et al (2018): Rev. Sci. Instrum. issn 0034-6748, doi :10.1063/1.5027608
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT018
About •	Received ※ 14 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT037	Beam Measurement and Application of the Metal Vapor Vacuum Arc Ion Source at KOMAC	radiation, ion-source, extraction, experiment	328
	S.H. Lee, H.S. Kim, H.-J. Kwon KOMAC, KAERI, Gyeongju, Republic of Korea
	Funding: This work has been supported through KOMAC operation fund of KAERI by MSIT (Ministry of Science and ICT) and the NRF (National Research Foundation) of Korea grant fund the Korea government (MSIT). The metal ion beam facility is developed based on the MEVVA* ion source at the KOMAC*. The MEVVA ion source has advantage that it can be extract almost metal ion species as well as high current ion beam. After the installation, we measured beam properties such as peak beam current, beam profile depending on the operation condition. The average charge state is measured in order to estimate the total dose. We evaluate the beam stability through the long-term beam extraction, and the measured the cathode erosion rate too. In addition, as one of the application fields, we irradiate the metal beam on the cathode of the fuel cell and measured the performance. In this paper, the beam measurement results, are summarized and fuel cell performances after metal beam irradiation are discussed. Korea Multi-purpose of Accelerator Complex **Metal Vapor Vacuum Arc
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT037
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT048	Design of a Prototype Gas Jet Profile Monitor for Installation Into the Large Hadron Collider at CERN	electron, proton, experiment, photon	363
	R. Veness, M. Ady, C. Castro Sequeiro, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski CERN, Meyrin, Switzerland P. Forck, S. Udrea GSI, Darmstadt, Germany N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom
	The Beam-Gas Curtain or BGC is the baseline instrument for monitoring the concentricity of the LHC proton beam with a hollow electron beam for the hollow e-lens (HEL) beam halo suppression device which is part of the High-Luminosity LHC upgrade. The proof-of-principles experiments of this gas-jet monitor have now been developed into a prototype instrument which has been built for integration into the LHC ring and is now under phased installation for operation in the upcoming LHC run. This paper describes the challenges overcome to produce a gas-jet fluorescence monitor for the ultra-high vacuum accelerator environment. It also presents preliminary results from the installation of the instrument at CERN.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT048
About •	Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT054	A Modified Nomarski Interferometer to Study Supersonic Gas Jet Density Profiles	laser, experiment, optics, diagnostics	385
	C. Swain, O. Apsimon, A. Salehilashkajani, C.P. Welsch, J. Wolfenden, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom Ö. Apsimon, A. Salehilashkajani, C. Swain, C.P. Welsch, J. Wolfenden, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom
	Funding: This work is supported by the AWAKE-UK phase II project grant No. ST/T001941/1, the STFC Cockcroft core grant No. ST/G008248/1 and the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1. Gas jet-based non-invasive beam profile monitors, such as those developed for the high luminosity Large Hadron Collider (HL-LHC) upgrade, require accurate, high resolution methods to characterise the supersonic gas jet density profile. This paper proposes a modified Nomarski interferometer to non-invasively study the behaviour of these jets, with nozzle diameters of 1 mm or less in diameter. It discusses the initial design and results, alongside plans for future improvements. Developing systems such as this which can image on such a small scale allows for improved monitoring of supersonic gas jets used in several areas of accelerator science, thus allowing for improvements in the accuracy of experiments they are utilised in.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT054
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT056	Commissioning of a Gas Jet Beam Profile Monitor for EBTS and LHC	electron, photon, simulation, MMI	393
	H.D. Zhang, N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom M. Ady, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski, R. Veness CERN, Meyrin, Switzerland P. Forck, S. Udrea GSI, Darmstadt, Germany N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom
	Funding: This work is supported by the HL-LHC-UK II project funded by STFC and CERN and the STFC Cockcroft core grant No. ST/G008248/1. A gas jet beam profile monitor was designed for measuring the electron beam at the electron beam test stand (EBTS) for the Hollow electron lens (HEL) and the proton beam in the large hadron collider (LHC). It is partially installed in the LHC during the second long shutdown. The current monitor is tailored to the accelerator environment including vacuum, geometry, and magnetic field for both the EBTS and the LHC. It features a compact design, a higher gas jet density, and a wider curtain size for a better integration time and a larger detecting range. In this contribution, the commissioning of this monitor at the Cockcroft Institute will be discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT056
About •	Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK043	Wakefield Effects Evaluation on Nanometer Small Beam at KEK-ATF	wakefield, simulation, alignment, cavity	556
	Y. Abe, K. Kubo, T. Okugi, N. Terunuma Sokendai, Ibaraki, Japan K. Kubo, T. Okugi, N. Terunuma KEK, Ibaraki, Japan
	Funding: This work was supported by JST, the establishment of university fellowships towards the creation of science technology innovation, Grant Number JPMJFS2136. This work was also supported by JST SPRING, Grant Number SDP221102. Accelerator Test Facility (ATF) is R&D facility to evaluate final focus technology for small beam required by ILC. The final focus beamline(ATF2) sets the goal to achieve 37 nm vertical beam size and 41 nm beam size had been demonstrated. Moreover, a significant intensity dependence on a nanometer beam size was observed and several studies of the wakefield had been conducted [,,*]. ATF2 is a proper beamline for wakefield studies with low emittance beam and nanometer resolution cavity BPMs and a nanometer beam size monitor. The simulation results were qualitatively cross-checked with experimental results and showed that the effects of some vacuum components and BPMs were significant. Further analysis of the wakefield will be done for flexible components (e.g. bellows). An upgrade of the ATF2 beamline is proposed by including minimization of the wakefield sources, to establish technologies for stable nanometer beam. J.Snuverink et al., PHYS. REV.ACCEL. BEAMS19, 091002. T.Okugi et al., PASJ16, FRPI023, 2019. *P.Korysko et al., PHYS. REV.ACCEL. BEAMS23, 121004.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK043
About •	Received ※ 20 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS004	Optimizing Activation Recipe with Cs, Te, O for GaAs-Based Photocathodes	cathode, electron, site, polarization	628
	J. Bae, M.B. Andorf, I.V. Bazarov, A. Galdi, J.M. Maxson Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA L. Cultrera BNL, Upton, New York, USA
	Funding: Department of Energy (DOE) DE-SC0021039. GaAs-based photocathodes are the most popular electron sources for producing highly spin-polarized electron beams in accelerator physics and condensed matter physics. Spin-polarized photoemission requires activation to achieve Negative Electron Affinity (NEA). Conventional NEA surfaces such as CS-O/NF3 are extremely vacuum sensitive, and this results in rapid QE degradation. In this work, we activated GaAs with various recipes using Cs, Te, and oxygen. We demonstrate NEA activation on GaAs surfaces. Among Cs-Te activated samples, the oxidized sample showed the highest QE and longest lifetime at 780 nm.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS004
About •	Received ※ 04 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS007	Optimized Dielectric Loaded Waveguide Terahertz LINACs	electron, acceleration, linac, GUI	634
	M. Vahdani University of Hamburg, Hamburg, Germany M. Fakhari DESY, Hamburg, Germany F.X. Kärtner The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany F.X. Kärtner Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany M. Vahdani CFEL, Hamburg, Germany
	Dielectric loaded waveguides (DLW) powered by multicycle terahertz (THz) pulses have shown promising performance as compact linear accelerators due to higher breakdown fields at THz frequencies compared to conventional RF components. By changing the dielectric dimensions one can control phase and group velocities of the THz pulse inside the DLW. Since optimum waveguide dimensions are dependent on initial electron energy, THz pulse energy, and etc., it is worthwhile to determine optimum values for different conditions to maximize final kinetic energy. In this work, we present a combined analytical/numerical guide to determine the optimum DLW parameters for single on-axis electron acceleration. We also introduce normalized graphic representations to visualize optimum designs for different initial electron and THz pulse energies.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS007
About •	Received ※ 09 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS019	The New SPARC_LAB RF Photo-Injector	gun, operation, solenoid, quadrupole	671
	D. Alesini, M.P. Anania, M. Bellaveglia, A. Biagioni, F. Cardelli, G. Costa, M. Del Franco, G. Di Pirro, L. Faillace, M. Ferrario, G. Franzini, A. Gallo, A. Giribono, L. Piersanti, L. Sabbatini, A. Stella, A. Vannozzi INFN/LNF, Frascati, Italy A. Battisti, E. Chiadroni, G. Di Raddo, A. Liedl, V.L. Lollo, L. Pellegrino, R. Pompili, S. Romeo, V. Shpakov, C. Vaccarezza, F. Villa LNF-INFN, Frascati, Italy M. Carillo, E. Chiadroni Sapienza University of Rome, Rome, Italy A. Cianchi, M. Galletti Università di Roma II Tor Vergata, Roma, Italy
	A new RF photo-injector has been designed, realized and successfully installed at the SPARC_LAB facility (INFN-LNF, Frascati, Rome). It is based on a 1.6 cell RF gun fabricated with the new brazing free technology recently developed at the National Laboratories of Frascati. The electromagnetic design has been optimized to have a full compensation of the dipole and quadrupole field components introduced by the coupling hole with an improvement of the effective pumping speed with two added pumping ports. The gun is overcoupled (\beta=2) to reduce the filling time and to allow the operation with short RF pulses. The overall injector integrates a new solenoid with a remote control of the transverse position and a variable skew quadrupole for the compensation of residual quadrupole field components. It also allows an on axis laser injection system with the last mirror in air, and the possibility of a future integration of an X/C band cavity linearizer. In the paper we report the main characteristics of the electromagnetic and mechanical design and the low and high power test results that shows the extremely good perfomances of the new device.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS019
About •	Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS034	Material Normal Energy Distribution for Field Emission Analyses From Monocrystalline Surfaces	electron, lattice, framework, cathode	713
	J.I. Mann, Y. Li, J.B. Rosenzweig UCLA, Los Angeles, California, USA T. Arias, J.K. Nangoi Cornell University, Ithaca, New York, USA
	Funding: National Science Foundation Grant No. PHY-1549132 Electron field emission is a complicated phenomenon which is sensitive not only to the particular material under illumination but also to the specific crystalline orientation of the surface. Summarizing the ability for a crystal to emit in a particular direction would be of great use when searching for good field emitters. In this paper we propose a material normal energy distribution which describes the ability of the bound electrons to tunnel under an intense electric field. This framework breaks a computationally expensive 3-D system down to a source distribution representation applicable for more efficient 1-D models. We use the Fowler-Nordheim framework to study the yield and MTE (mean transverse energy) from sources including gold, copper, and tungsten in both monocrystalline and polycrystalline forms. We find an increase in effective work function for field emission in the (111) direction for gold and copper associated with the Bragg plane intersections of the Fermi surface.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS034
About •	Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 06 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS036	Simulations of Laser Field Emission from Nanostructures with Image Charge Trapping and Band Structure Transitions	electron, laser, simulation, photon	717
	B. Wang, G.E. Lawler, J.I. Mann, J.B. Rosenzweig UCLA, Los Angeles, California, USA T. Arias, J.K. Nangoi Cornell University, Ithaca, New York, USA S.S. Karkare Arizona State University, Tempe, USA
	Funding: National Science Foundation Grant No. PHY-1549132 Laser-induced field emission from nanostructures as a means to create high brightness electron beams has been a continually growing topic of study. Experiments using nanoblade emitters have achieved peak fields upwards of 40 GV/m, begging further investigation in this extreme regime. A recent paper has provided analytical reductions of the common semi-infinite Jellium system for pulsed incident lasers. We utilize these results as well as similar previous results to further understand the physics underlying electron rescattering-type emissions. We progress in numerically evaluating the analytical solution to attempt to more efficiently generate spectra for this system. Additionally, we use the full 1-D time-dependent Schrödinger equation with a Hartree potential and a dispersion-relation transition from material to vacuum to study the same system. We determine what importance the inclusion of the material band structure may have on emissions using this computationally challenging approach.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS036
About •	Received ※ 08 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS045	Vacuum Control System Upgrade for ALPI Accelerator	controls, PLC, hardware, EPICS	744
	G. Savarese, L. Antoniazzi, D. Bortolato, A. Conte, F. Gelain, D. Marcato, C.R. Roncolato INFN/LNL, Legnaro (PD), Italy
	The vacuum system of ALPI accelerator includes about 40 pumping groups based on turbomolecular pumps. The instrumentation of the accelerators complex is mainly the one installed in 90s, with consequent maintenance issues. The control and supervision systems were developed in the same period by an external company, which produced custom solutions for the HW and SW parts. Control devices are based on custom PLCs, while the supervision system is based on C and C#. The communication between the field and the supervisor is composed of multiple levels: RS-232 standard is used to transfer control parameter from the field devices up to custom multiplexers; RS-485 transmission is used from the multiplexers to two PC servers covering different sections of the installation; while Ethernet, is used to connect the servers and the operation console. Obsolescence and rigidity of the system, deficit of spare parts and impossibility of reparation or modification without external support, required a complete renovation of the vacuum system and relative controls in the next years. This paper describes the adopted strategy and the implementation status.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS045
About •	Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS047	Control and Functional Safety Systems Design for Real-Time Conditioning of RF Structures at TEX	controls, EPICS, interface, framework	751
	S. Pioli, R. Gargana, D. Moriggi LNF-INFN, Frascati, Italy F. Cardelli, P. Ciuffetti, C. Di Giulio INFN/LNF, Frascati, Italy
	We report the status of the development of an High Power RF Laboratory in X-Band called TEX (TEst-stand for X-Band). TEX is part of the LATINO (Laboratory in Advanced Technologies for INnOvation) initiative that is ongoing at the Frascati National Laboratories (LNF) of the Italian Institute for Nuclear Physics (INFN) that covers many different areas focused on particle accelerator technologies. TEX is a RF test facility based on solid-state K400 modulator from ScandiNova with a 50MW class X-band (11.994 GHz) klystron tube model VKX8311A operating at 50 Hz. This RF source will operate as resource for test and research programs such as the RF breakdown on RF waveguide components as well as high power testing of accelerating structures for future high gradient linear accelerator such as EuPRAXIA and CLIC. In this context we will present the whole EPICS control system design focusing on archiving, user interfaces and custom development made as part of the functional safety to deliver real-time RF breakdown detection integrated with the timing system of the facility.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS047
About •	Received ※ 16 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOPLGD2	SPS-II: A 4th Generation Synchrotron Light Source in Southeast Asia	storage-ring, synchrotron, lattice, photon	764
	P. Klysubun, S. Boonsuya, T. Chanwattana, S. Jummunt, N. Juntong, A. Kwankasem, T. Phimsen, P. Photongkam, S. Prawanta, T. Pulampong, K. Sittisard, S. Srichan, P. Sudmuang, P. Sunwong, O. Utke SLRI, Nakhon Ratchasima, Thailand
	Upon its completion, Siam Photon Source II (SPS-II) will be the first 4th generation synchrotron light source in Southeast Asia. The 3.0 GeV, 327.5 m storage ring based on the Double-Triple Bend Achromat lattice will have the natural emittance of 0.97 nm·rad. The storage ring includes 14 long and 14 short straight sections for insertion devices and machine subsys-tems. The beam injection will be performed by a 150 MeV linear accelerator and a full-energy concentric booster synchrotron sharing the same tunnel with the storage ring. In the first phase, there will be 7 insertion devices and 7 associated beamlines with the end sta-tions for different techniques utilizing synchrotron radiation from 80 eV to 60 keV. High-energy and high-brightness radiation generated by the new light source will serve as one of the most powerful analytical tools in the region for advanced science and technology research.
	Slides MOOPLGD2 [4.168 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOOPLGD2
About •	Received ※ 12 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOPT014	The Status of the SASE3 Variable Polarization Project at the European XFEL	undulator, polarization, FEL, radiation	1029
	S. Karabekyan, S. Abeghyan, M. Bagha-Shanjani, S. Casalbuoni, U. Englisch, W. Freund, G. Geloni, J. Grünert, S. Hauf, C. Holz, D. La Civita, J. Laksman, D. Mamchyk, M.P. Planas, F. Preisskorn, S. Serkez, H. Sinn, M. Wuenschel, M. Yakopov, C. Youngman EuXFEL, Schenefeld, Germany P. Altmann, A. Block, W. Decking, L. Fröhlich, O. Hensler, T. Ladwig, D. Lenz, D. Lipka, R. Mattusch, N. Mildner, E. Negodin, J. Prenting, F. Saretzki, M. Schlösser, F. Schmidt-Föhre, E. Schneidmiller, M. Scholz, D. Thoden, T. Wamsat, T. Wilksen, T. Wohlenberg, M.V. Yurkov DESY, Hamburg, Germany J. Bahrdt HZB, Berlin, Germany M. Brügger, M. Calvi, S. Danner, R. Ganter, L. Huber, A. Keller, C. Kittel, X. Liang, S. Reiche, M.S. Schmidt, T. Schmidt, K. Zhang PSI, Villigen PSI, Switzerland D.E. Kim PAL, Pohang, Republic of Korea Y. Li IHEP, People’s Republic of China
	The undulator systems at the European XFEL consist of two hard X-ray systems, SASE1 and SASE2, and one soft X-ray system, SASE3. All three systems are equipped with planar undulators using permanent neodymium magnets. These systems allow the generation of linearly polarized radiation in the horizontal plane. In order to generate variable polarization radiation in the soft X-ray range, an afterburner is currently being implemented behind the SASE3 planar undulator system. It consists of four APPLE-X helical undulators. The project, called SASE 3 Variable Polarization, is close to being put into operation. All four helical undulators have been installed in the tunnel during the 2021-2022 winter shutdown. This paper describes the status of the project and the steps toward its commissioning. It also presents lessons learned during the implementation of the project.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT014
About •	Received ※ 02 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOPT024	Recent Developments at SOLARIS National Synchrotron Radiation Centre	synchrotron, radiation, operation, plasma	1051
	A.I. Wawrzyniak, P. Andryszczak, G. Cios, K. Gula, G.W. Kowalski, A.M. Marendziak, A. Maximenko, R. Panaś, T. Sobol, M. Szczepaniak, J.J. Wiechecki, M. Wiśniowski, M. Zając NSRC SOLARIS, Kraków, Poland A. Curcio CLPU, Villamayor, Spain H. Lichtenberg Hochschule Niederrhein University of Applied Sciences, Krefeld, Germany
	SOLARIS National Synchrotron Radiation Centre is under constant development of the research infrastructure. In 2018 first users were welcomed at three different experimental stations. Up to now 5 end stations are available at SOLARIS for experiments at 4 beamlines, and 4 new beamlines are under construction. In 2021 new front end for POLYX beamline was installed and de-gassed. Moreover, ASTRA beamline components were installed and first commissioning stage has stared. Additionally, a plasma cleaning station has been designed, built and is currently tested. Apart of the beamlines, up-grades to the linac and storage ring operation have been done. During the COVID-19 pandemic the software for remote injection process was developed and is used on daily basis. The transverse beam emittance measurement on the visible light beamline LUMOS was implemented and gives results that are complementary to the Pinhole beamline. Within this presentation the overview of the recent developments with insight to the details to be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT024
About •	Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK003	High Power RF Conditioning of the ESS RFQ	rfq, cavity, operation, interlocks	1189
	O. Piquet, A.C. Chauveau, P. Hamel CEA-IRFU, Gif-sur-Yvette, France M. Baudrier, M.J. Desmons CEA-DRF-IRFU, France B. Jones, D. Noll, A.G. Sosa, E. Trachanas, R. Zeng ESS, Lund, Sweden
	The 352.21 MHz Radio Frequency Quadrupole (RFQ) for the European Spallation Source ERIC (ESS) has been delivered by the end of 2019 by CEA/IRFU. The RFQ is designed to accelerate a 70 mA proton beam from 75 keV up to 3.62 MeV. It consists of a 4-vane resonant cavity with a total length of 4.6 m. Two coaxial power loop couplers feed the RFQ with the 1.4 MW of RF power required for beam operation. This paper first presents the main systems required for the RFQ conditioning. Then it summarizes the main steps and results of this high power RF conditioning completed at ESS from June 9 to July 29, 2021 in order to achieve the nominal field for a pulse length of 3.2ms at the repetition rate of 14Hz.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK003
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 09 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK009	Development of Superconducting CH Cavity Preparation at IAP	cavity, simulation, coupling, ECR	1208
	P. Müller, H. Podlech IAP, Frankfurt am Main, Germany K. Aulenbacher, F.D. Dziuba, V. Gettmann, T. Kürzeder, M. Miski-Oglu HIM, Mainz, Germany W.A. Barth, M. Basten, V. Gettmann, T. Kürzeder, M. Miski-Oglu GSI, Darmstadt, Germany
	Funding: HIC for FAIR, BMBF Contr. No. 05P21RFRB2 and HFHF Goethe University (GU), Gesellschaft für Schwerionenforschung (GSI) and Helmholtz Institut Mainz (HIM) work in collaboration on the Helmholtz Linear Accelerator (HELIAC). A new superconducting (sc) continous wave (cw) high intensity heavy ion linear accelerator (Linac) will provide ion beams with maximum duty factor up to beam energies of 7.3 MeV/u. The acceleration voltage will be provided by sc Crossbar-H-mode (CH) cavities, developed of Institute for Applied Physics (IAP) at GU. Cavity preparation is researched and optimized towards widely used elliptical multicell cavities. A standardized preparation protocol for CH cavities is researched in collaboration between GU, GSI and HIM on a 360 MHz 19 gap CH prototype. Baseline measurements and a 120°C 48 hour bake produced higher maximum gradient, higher intrinsic quality factor and a shorter cavity conditioning phase. As a critical preparation step, High Pressure Rinsing (HPR) with ultra pure water will be performed at HIM and is currently in preparation. HPR cycles are currently tested on a CH dummy with a new nozzle layout that is optimized towards CH cavity geometry.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK009
About •	Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 02 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK012	Nitrogen Infusion Sample R&D at DESY	cavity, niobium, ECR, accelerating-gradient	1219
	C. Bate University of Hamburg, Hamburg, Germany A. Ermakov, D. Reschke, J. Schaffran DESY, Hamburg, Germany W. Hillert, M. Wenskat University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
	Funding: This work was supported by the Helmholtz Association within the topic Accelerator Research and Development (ARD) of the Matter and Technologies (MT) Program. Many accelerator projects such as the ILC would benefit from cavities with reduced surface resistance (high Q-values) while maintaining a high accelerating gradient. A possible way to meet the requirements is the so-called nitrogen-infusion procedure on Niobium cavities. However, a fundamental understanding and a theoretical model of this method are still missing. One important parameter is the residual resistance ratio (RRR) which is related to the impurity content of the material. We report the investigated RRR on samples in a wide temperature range in a vacuum and under a nitrogen atmosphere. This comparison made it possible to make statements about the differences in the concentration of nitrogen by varying the temperature. The samples are pure cavity-grade niobium and treated in the same manner as cavities. For this purpose, a small furnace dedicated to sample treatment was set up to change and explore the parameter space of the infusion recipe. Care was taken to achieve the highest level of purity possible in the furnace and in a pressure range of 1.0·10^-8 mbar in order to meet the high requirements of nitrogen infusion.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK012
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK018	Combined In-Situ QEXAFS and XRD Investigations on Nb-Treatments in N₂ Gas Atmospheres at Elevated Temperatures	site, cavity, niobium, SRF	1238
	P. Rothweiler, F. Eckelt, D. Lützenkirchen-Hecht, S. Paripsa, L. Voß University of Wuppertal, Wuppertal, Germany
	Funding: We gratefully acknowledge financial support by the German Federal Ministry of Education and Research (BMBF) under project No. 05H18PXRB1. Thin polycrystalline Nb metal foils were treated in N₂ gas atmospheres at elevated temperatures of 900 °C up to 1200 °C. A combination of transmission mode Quick X-ray absorption spectroscopy (QEXAFS) at the Nb-K-edge and X-ray diffraction (XRD) used in parallel were used to investigate changes in the atomic short and long-range structure of the bulk Nb-material in-situ. A dedicated high-vacuum heating cell with a base pressure of 10^-6 mbar was used to perform the heat treatments under vacuum and nitrogen gas atmosphere. The treatments typically included (i) a preheating at 900 °C under high-vacuum, (ii) a treatment in 3 mbar nitrogen gas at the desired temperature and (iii) a cooldown to room temperature under vacuum conditions. The QEXAFS and XRD data were collected in parallel during the entire process with a time resolution of 4 s. While the samples treated at 900 °C show the typical N-uptake to the octahedral interstitial sites, the samples treated at higher temperatures show the growth of distinct niobium nitride phases. The results will be discussed in more details during the conference.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK018
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK025	Design Study of the Third Harmonic Superconducting Cavity for a Bunch Lengthening	cavity, superconducting-cavity, status, HOM	1258
	J.Y. Yoon, E.-S. Kim KUS, Sejong, Republic of Korea J.H. Han, H.S. Park Kiswire Advanced Technology Ltd., Daejeon, Republic of Korea E. Kako KEK, Ibaraki, Japan
	The bunch lengthening by the 3rd harmonic cavity reduces the electron collisions in a bunch and increases the Touschek lifetime of a storage ring. We performed the multi-physics simulations including the electromagnetic, thermal, and mechanical analysis of the cavity. In the electromagnetic simulation, the geometry is optimized for the required performance of the cavity. The elliptical double-cell geometry is selected to increase the accelerating voltage and reduce the power losses of the cavity. Thermal/mechanical analyses were performed to check the deformation of the thermal and pressure contraction. The prototype cavity does not require the power coupler as it is a passive type. The conceptual design and copper prototype of the 3rd harmonic cavity will be described in this paper. Based on this design, the fabrication of Niobium cavity is in progress. Superconducting RF, Cavity
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK025
About •	Received ※ 02 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 09 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK026	ESS Elliptical Cryomodules Tests at Lund Test Stand	cavity, cryomodule, operation, LLRF	1261
	C.G. Maiano, E. Asensi Conejero, N. Elias, P. Goudket, W. Hees, P. Pierini, L. Sagliano, F. Schlander, M.Y. Wang ESS, Lund, Sweden D. Bocian, W. Gaj, P. Halczynski, M. Sienkiewicz, F.D. Skalka, J. Swierblewski, K.M. Wartak, M. Wartak IFJ-PAN, Kraków, Poland
	We present an overview and description of the elliptical cryomodules test activities at Lund Test Stand 2. During 2021 the test facility was commissioned with one prototype, and four series medium beta modules have now been successfully tested at ESS in Lund. This activity allowed the joint ESS and IFJ PAN team to develop all the procedures and the necessary automated tools for the different phases of the site acceptance test campaign (e.g. incoming inspections, coupler conditioning, cooldown strategies, tuning to resonance and electromagnetic/cryogenic performance verification). During the initial test period techniques for diagnostics of limiting mechanisms have been developed and improved up to a consolidated and mature state for the rest of the test campaign. Tests results and the initial statistics is presented and commented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK026
About •	Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK042	Challenges to Reliable Production Nitrogen Doping of Nb for SRF Accelerating Cavities	cavity, niobium, SRF, controls	1311
	C.E. Reece, M.J. Kelley, E.M. Lechner, A.D. Palczewski JLab, Newport News, Virginia, USA J.W. Angle, M.J. Kelley Virginia Polytechnic Institute and State University, Blacksburg, USA F.A. Stevie NCSU AIF, Raleigh, North Carolina, USA
	Funding: This work was authored by JSA LLC under U.S. DOE contract DE-AC05-06OR23177. This material is based on work supported by the U.S. DOE Early Career Award to A. Palczewski, with supplemental support from DOE BES via the LCLS-II HE R&D program. J. Angle’s support was from the Office of High Energy Physics, under grant DE-SC-0014475 to Virginia Tech. Over the last several years, alloying of the surface layer of niobium SRF cavities has been demonstrated to beneficially lower the superconducting RF surface resistance. Nitrogen, titanium, and oxygen have all been demonstrated as effective alloying agents, occupying interstitial sites in the niobium lattice within the RF penetration depth and even deeper, when allowed to thermally diffuse into the surface at appropriate temperatures. The use of nitrogen for this function has been often termed ’nitrogen doping’ and is being applied in the LCLS-II and LCLS-II HE projects. We report characterization studies of the distribution of nitrogen into the exposed niobium surface and how such distribution is affected by the quality of the vacuum furnace environment in which the doping takes place, and the complexity of nitride crystal growth on different grain orientations of surface niobium. Using state-of-the-art quantification methods by dynamic secondary ion mass spectrometry (SIMS) depth profiling in niobium, we identify several phenomena involving furnace-sourced contamination. We also highlight a potential issue with N₂ flow constraints from the flange ’caps’ used during heat treatments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK042
About •	Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK052	Influence of a Positive Grid Biasing on RF System in J-PARC RCS	controls, acceleration, power-supply, operation	1336
	M. Yamamoto, M. Nomura, H. Okita, T. Shimada, F. Tamura JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan K. Hara, K. Hasegawa, C. Ohmori, Y. Sugiyama, M. Yoshii KEK, Tokai, Ibaraki, Japan
	In order to accelerate a high intensity beam in the RCS, a large amplitude of the anode current is provided by a tube amplifier to compensate a heavy beam loading. Tetrode vacuum tubes are used in the RCS, and the control grid voltage enters into a positive region to feed such a large current. The positive grid biasing affects the waveform of the control grid voltage; it is deformed due to the induced control grid current under the condition of the multi-harmonic rf driving. Furthermore, the DC bias voltage drop on the control grid is observed because of the exceeding the ability for the control grid power supply. We describe the influence of the positive grid biasing in the RCS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK052
About •	Received ※ 06 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK059	Modeling O and N Alloying in Nb for SRF Applications	cavity, SRF, niobium, radio-frequency	1354
	E.M. Lechner, M.J. Kelley, A.D. Palczewski, C.E. Reece JLab, Newport News, Virginia, USA J.W. Angle, M.J. Kelley Virginia Polytechnic Institute and State University, Blacksburg, USA F.A. Stevie NCSU AIF, Raleigh, North Carolina, USA
	Funding: This work was coauthored by Jefferson Science Associates LLC under U.S. DOE Contract No. DE-AC05-06OR23177 and grant No. DE-SC-0014475 to Virginia Tech for the support of J. Angle. N and O-alloyed superconducting radio frequency cavities exhibit extraordinary quality factors. Developing diffusion models that describe interstitial N and O in Nb is important for optimizing alloyed cavity quality factors and accelerating gradients. N and O-alloyed Nb samples are examined with SEM AND SIMS and their diffusion profiles modeled.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK059
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS005	SOLEIL Machine Status and Upgrade	injection, lattice, photon, synchrotron	1397
	L.S. Nadolski, G. Abeillé, Y.-M. Abiven, F. Bouvet, P. Brunelle, N. Béchu, M.-E. Couprie, X. Delétoille, S. Duigou, A. Gamelin, C. Herbeaux, N. Hubert, M. Labat, J.-F. Lamarre, V. Le Roux, A. Lestrade, A. Loulergue, O. Marcouillé, F. Marteau, A. Nadji, R. Nagaoka, M. Nouna, Y. Rahier, F. Ribeiro, G. Schaguene, K. Tavakoli, M.-A. Tordeux SOLEIL, Gif-sur-Yvette, France S. Ducourtieux LNE, Trappes Cedex, France
	SOLEIL is both a 2.75 GeV third generation synchrotron light source and a research laboratory at the forefront of experimental techniques dedicated to matter analysis down to the atomic scale, as well as a service platform open to all scientific and industrial communities. We present the performance of the accelerators delivering extremely stable photon beams to 29 beamlines. We report on the commissioning of a superbend magnet replacing a standard 1.71T dipole with a 2.84 T narrow peak permanent magnet-based dipole. It required local modification of the lattice to compensate linear and nonlinear optics distortions introduced by the new magnet field. The latest measurements made with a Multipole Injection Kicker are also reported. Work on the NEG test bench and its dedicated front-end for a 10 mm inner diameter vacuum pipe and other major R&D areas are also addressed in the frame of the SOLEIL upgrade.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS005
About •	Received ※ 10 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS011	Progress Towards EEHG Seeding at the DELTA Storage Ring	laser, electron, undulator, storage-ring	1420
	B. Büsing, A. Held, H. Kaiser, S. Khan, C. Mai, A. Radha Krishnan DELTA, Dortmund, Germany
	Funding: Funded by BMBF (05K16PEB, 05K19PEB), FZ Jülich, and by the federal state NRW. Seeding of free-electron lasers (FELs) with external laser pulses triggers the microbunching process such that the spectrotemporal properties of coherently emitted FEL radiation are under better control compared to self-amplified spontaneous emission. High-gain harmonic generation (HGHG) based on the interaction of electrons with a single laser pulse is routinely applied at a few FELs, and echo-enabled harmonic generation (EEHG) with a twofold laser-electron interaction has been demonstrated. Both schemes can be adopted in storage rings for the coherent emission of ultrashort radiation pulses. Coherent harmonic generation (CHG) is the counterpart to HGHG without FEL gain. It has been employed at several storage rings and presently provides ultrashort pulses in the vacuum ultraviolet regime at the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University. EEHG, which allows to reach higher harmonics of the seed wavelength, has not yet been implemented at any storage ring but is pursued at DELTA as an upgrade plan. The paper presents the layout of the envisaged EEHG facility, and it reviews simulation studies and the technical progress towards EEHG seeding at DELTA.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS011
About •	Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 29 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS015	Proposal of a Girder Realignment Test in PETRA III	alignment, controls, storage-ring, experiment	1435
	M. Schaumann, I.V. Agapov, R. Bartolini, M. Bieler, R. Böspflug, D. Einfeld, M.G. Hoffmann, J. Keil, L. Liao, G. Priebe, M. Schlösser, R. Wanzenberg DESY, Hamburg, Germany
	PETRA IV can benefit from the fine control of the girders that carry the storage ring elements to achieve the design beam performance. Based on the corrector magnet strength pattern it is desired to realign girders to stay within the alignment tolerances. In the current PETRA III configuration, the girders in the Max von Laue Hall are equipped for remote alignment, however, those have not been moved since their initial installation and the alignment system is currently not connected to the control system. In preparation for PETRA IV, a movement test of one of the PETRA III girders should confirm the ability to safely and precisely remote control the equipment based on an optics model that describes the effect of the girder movement on the orbit. This paper studies the feasibility of this test and prepares an initial mock-up experiment to be performed on a spare girder.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS015
About •	Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS022	Cooling Challenges in a NEG-Coated Vacuum Chamber of a Light Source	simulation, radiation, software, synchrotron	1456
	S. Talebi Motlagh, A. Danaeifard, J. Rahighi, F. Saeidi ILSF, Tehran, Iran F. Zamani University of Kashan, Kashan, Iran
	In a light Source, unused synchrotron radiation is being distributed along the walls of the chambers. Due to the small conductance of the chambers, vacuum pumping is based on the distributed concept, and then non-evaporable getter (NEG) coating is extensively used. The vacuum chambers are made of copper alloys tube, and cooling circuits are welded to the chamber to remove the heat load from the radiation generated. Filler metal is used to create a brazed joint between the water cooling pipe and the vacuum chamber body. The thermal conductivity of the fillers is less than the vacuum chamber body. Moreover, the water velocity in the cooling pipe must be taken into account in thermal calculations. In this paper, we study and investigate the effects of the filler metal and the cooling water velocity in cooling the chambers.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS022
About •	Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS052	Considerations From Deploying, Commissioning, and Maintaining the Control System for LCLS-II Undulators	undulator, controls, MMI, EPICS	1546
	M.A. Montironi, C.J. Andrews, G. Marcus, H.-D. Nuhn SLAC, Menlo Park, California, USA
	Funding: This work was supported by Department of Energy, Office of Basic Energy Sciences, contract DE-AC02-76SF00515 Two new undulator lines have been installed as part of the Linac Coherent Light Source upgrade (LCLSII) at SLAC National Accelerator Laboratory. One undulator line, composed of 21 horizontally polarizing undulator segments, is dedicated to producing Soft X-Rays (SXR). The other line, composed of 32 vertically polarizing undulator segments, is dedicated to producing Hard X-Rays (HXR). The devices were installed, and the control system was deployed in 2019. Commissioning culminated with the achievement of first light from the HXR undulator in the Summer of 2020 and from the SXR undulator in the Fall of 2020. Since then, both undulator lines have been successfully providing x-Rays to user experiments with very limited downtime. In this paper, we first describe the strategies utilized to simplify the deployment, commissioning, and maintenance of the control system. Such strategies include scripts for automated components calibration and monitoring, a modular software structure, and debugging manuals for accelerator operators. Then, we discuss lessons learned which could be applicable to similar projects in the future.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS052
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIYSP1	New Designs of Short-Period Undulators for Producing High-Brightness Radiation in Synchrotron Light Sources	undulator, radiation, cryogenics, synchrotron	1624
	E.J. Wallén LBNL, Berkeley, California, USA
	We review modern state-of-the-art and new concepts of undulators planned for new generation light sources. Both superconducting and permanent-magnet-based insertion devices feature unique solutions to reach high precisely tunable fields in the period range of 10^-18 mm, 2-4 meters in length and with the ID gaps of less than 5 mm. The same quest for small gaps and shortest possible period length exists also for elliptically polarizing undulators. A review of new designs in Europe, Asia and Americas will be in the focus of this presentation.
	Slides WEIYSP1 [21.171 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIYSP1
About •	Received ※ 15 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIZSP2	Trapping of Neutral Molecules by the Electromagnetic Beam Field	dipole, electron, simulation, alignment	1649
	G. Franchetti GSI, Darmstadt, Germany F. Zimmermann CERN, Meyrin, Switzerland
	Neutral uncharged molecules are affected by the electromagnetic field of a charged particle beam if they carry either an electric or a magnetic dipole moment. The residual gas in an accelerator beam pipe consists of such molecules. In this paper we study their dynamics. Under a few approximations, whose validity we explore and justify, we derive the equations of motion of neutral molecules and their invariants, determine the conditions for these neutral molecules to become trapped in the field of the beams as function of beam-pipe temperature, and compute the resulting enhancement of molecule density in the vicinity of the beam. We demonstrate that large agglomerates of molecules, "flakes," are much more likely to be pulled into the beam than single molecules, and suggest that this phenomenon might help explain some beam observations at the Large Hadron Collider.
	Slides WEIZSP2 [6.142 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIZSP2
About •	Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT045	Transverse Electron Beam Tails and Beam Lifetime in the EIC Electron Storage Ring	electron, simulation, proton, storage-ring	1958
	C. Montag BNL, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704. While for most storage ring design activities it is sufficient to assume a Gaussian distribution of the beam particles, a more detailed prediction of the population in the transverse tails is necessary to predict the beam lifetime in a given aperture. Dominant processes that result in non-Gaussian distributions are the beam-beam interaction in a collider as well as beam-gas scattering. Simulations to determine the required apertures and vacuum levels in the EIC electron storage ring will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT045
About •	Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK023	Simulation Study of Fast Extraction in the Absence of One Septum Magnet for J-Parc Main Ring	septum, operation, extraction, kicker	2100
	S. Iwata, S. Igarashi, K. Ishii, H. Matsumoto, N. Matsumoto, Y. Sato, T. Shibata, T. Sugimoto, T.Y. Yasui KEK, Tokai, Ibaraki, Japan
	At J-PARC main ring (MR), the two fast extracting beamlines to the neutrino facility and to the abort dump have a symmetrical layout of 6 septum magnets each, a total of 12. Since there are many magnets, it is necessary to be careful about failure. It is important to consider how to continue beam supply even if one of the septum mag-nets is missing. From July 2021, upgrade works of the FX septum magnets commenced with an aim of increasing the beam power of MR to 1.3 MW from 500 kW. We simulated the beam extraction without one of the septum magnets under the conditions of the new geometry of septum magnets and the new aperture. We found that the beam can be extracted by increasing the current of the surrounding septum magnets and compensating for the output.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK023
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK024	Upgrade of Septum Magnets for Fast Extraction in J-Parc Main Ring	septum, operation, extraction, power-supply	2103
	S. Iwata, K. Ishii, H. Matsumoto, N. Matsumoto, Y. Sato, T. Shibata, T. Sugimoto, M. Uota KEK, Tokai, Ibaraki, Japan
	We aim to supply a high-power proton beam of 1.3 MW to the neutrino facility from J-PARC Main Ring (MR) by shortening the repetition cycle to 1.16 s from 2.48 s and increasing the number of particles by 30%. The six sep-tum magnets for fast extraction (FX) need to be replaced to reduce the heat that is generated as a result of shorten-ing the repetition cycle. The replacement of the septum magnets began in July 2021 and was completed at the end of May 2022. The beam commissioning starts in June 2022. We report the details of the replacement work and operation test of the new septum magnets. We found a defect in the magnetic coil of the septum (SM32) in August 2021. We decided to postpone its installation to around August 2022 and produce new magnet coils for the SM32. The beam extraction in June 2022 will be per-formed using a temporary vacuum duct instead of the SM32 magnet, and the extraction beam orbit will be maintained by increasing the magnetic field of the other five septum magnets.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK024
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK052	Beam Coupling Impedance Study and Its Database of Siam Photon Source Storage Ring	impedance, storage-ring, wakefield, simulation	2177
	N. Juntong, T. Chanwattana, S. Jummunt, K. Kittimanapun, T. Phimsen, W. Promdee, T. Pulampong SLRI, Nakhon Ratchasima, Thailand
	Since the Siam Photon Source (SPS) had an electron beam energy upgraded from 1.0 GeV to 1.2 GeV in 2005, the storage ring impedance measurements were done once in 2007. Two insertion magnet devices have been installed in the SPS storage ring during June to August 2013. There are several vacuum components added to the storage ring; these affect the ring impedance. Quantitative understanding of instabilities requires detailed knowledge of the impedance of the ring. For this purpose, the development of an impedance database is a necessity, where the wake potentials of each vacuum component are kept and maintained in a standard format. The self-describing data sets (SDDS) file format will be utilized to record components wake potentials. The wake potentials of each vacuum component can be obtained from a particle tracking simulation; a CST particle studio program will be used in the simulation process. The wake potentials can also be included in a beam dynamic tracking program such as ELEGANT to observe beam behaviors with these instabilities and find a curing means. The study results will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK052
About •	Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK055	Beam Lifetime Measurements in Sirius Storage Ring	storage-ring, scattering, simulation, synchrotron	2186
	M.B. Alves, L. Liu, X.R. Resende, F.H. de Sá LNLS, Campinas, Brazil
	SIRIUS is the new storage ring-based 4th generation synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS) at the Brazilian Center for Research in Energy and Materials (CNPEM). In ultralow emittance storage rings such as SIRIUS, the dominant contribution to the beam lifetime is due to large angle scattering between electrons within the same bunch, namely the Touschek effect. We used the strategy of storing two bunches simultaneously with different currents to measure their Touschek lifetime independently of other contributions, such as gas scattering. The measurements were carried out in different conditions of bunch current and RF voltage to compare the experimental results with those expected from theory and simulations for SIRIUS.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK055
About •	Received ※ 08 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THIXSP1	A New Compact 3 GeV Light Source in Japan	cavity, electron, emittance, quadrupole	2402
	N. Nishimori QST, Tokai, Japan
	A new 3 GeV light source with a circumference of 350 m and an MBA lattice has been officially funded and is being constructed in north-eastern Japan. Aiming at stable and high-performance operations with an emittance of about 1 nm rad, various design and R&D activities are being performed: the four bend achromatic lattice using BQ combined function magnets; the compact RF system using a TM020 mode and in-cavity compact HOM absorbers; the in-vacuum off-axis injection scheme enabling stored beam oscillation-free injections with a small injection beam amplitude; the injector linac composed of a thermionic E-gun and C-band accelerators with a capability of extension to feed a future SX-FEL driver, and so on. The installation of accelerator components is ongoing. The talk will include the overall design of the light source, R&D results, and the latest construction status.
	Slides THIXSP1 [15.084 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THIXSP1
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST025	Operational Experience with the Improved VSR DEMO Collimating Shielded Bellow in BESSY II	operation, SRF, cavity, synchrotron	2497
	H.-W. Glock, V. Dürr, F. Glöckner, J. Knobloch, M. Ries, A. Vélez HZB, Berlin, Germany J. Knobloch University of Siegen, Siegen, Germany A. Vélez Technical University Dortmund, Dortmund, Germany
	Funding: Work supported by grants of the Helmholtz Association The Collimating Shielded Bellow (CsB) is designed to serve both as a flexible beam pipe connection between two adjacent superconducting cavities as foreseen in VSR DEMO and as a synchrotron light collimator to shield the down-stream cavity from synchrotron radiation. A convoluted inner RF shield was applied to prevent fundamental mode heating of the stainless-steel-made bellow in the cryogenic environment, making the such captured inner volume very difficult to access for inspection and cleaning. A first version of the device was successfully tested as part of the beam pipe of the synchrotron light source BESSY II under regular operation for more than a year. It suffered from an unfavorable long outgassing commissioning. Therefore a detachable design, allowing for rigorous inner surface preparation and cleaning, was built and recently installed in BESSY II. CsB version 2 design and experimental outcomes are described in the paper. First results indicated a significantly improved vacuum commissioning performance, which was confirmed later on.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST025
About •	Received ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST027	Fabrication of Robust Thermal Transition Modules and First Cryogenic Experiment with the Refurbished COLDDIAG	operation, cryogenics, diagnostics, experiment	2505
	H.J. Cha, N. Glamann, A.W. Grau, A.-S. Müller, D. Saez de Jauregui KIT, Eggenstein-Leopoldshafen, Germany
	Funding: This work is supported by the BMBF project 05H18VKRB1 HIRING (Federal Ministry of Education and Research). Two sets of thermal transition modules as a key component for the COLDDIAG (cold vacuum chamber for beam heat load diagnostics) refurbishment were manufactured, based on the previous design study. The modules are installed in the existing COLDDIAG cryostat and tested with an operating temperature of approximately 50 K at both a cold bore and a thermal shield. This cool-down experiment is a preliminary investigation aiming at beam heat-load studies at the FCC-hh where the beam screens will be operated at almost the same temperature. In this contribution, we report the fabrication processes of the mechanically robust transition modules and the first thermal measurement results with the refurbished COLDDIAG in a cryogenic environment. The static heat load in the refurbished cryostat remains unchanged, compared to that in the former one (4-K cold bore and 50-K shield with thin transitions), despite the increase in the transition thickness. It originates from the identical temperature at the cold bore and the shield, which can theoretically allow the heat intakes by thermal conduction and radiation between them to vanish.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST027
About •	Received ※ 16 May 2022 — Accepted ※ 13 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST035	Status of the Engineering Design of the IFMIF-DONES High Energy Beam Transport Line and Beam Dump System	target, beam-transport, diagnostics, neutron	2520
	D. Sánchez-Herranz, O. Nomen, M. Sanmartí, B.K. Singh IREC, Sant Adria del Besos, Spain F. Arranz, C. Oliver, I. Podadera CIEMAT, Madrid, Spain P. Cara IFMIF/EVEDA, Rokkasho, Japan V. Hauer KIT, Eggenstein-Leopoldshafen, Germany F. Ogando UNED, Madrid, Spain D. Sánchez-Herranz UGR, Granada, Spain
	Funding: Work performed within framework of EUROfusion Consortium, funded by European Union via Euratom Research & Training Programme (Grant Agreement 101052200’EUROfusion). Views & opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither European Union nor European Commission can be held responsible for them. IFMIF-DONES plant (International Fusion Materials Irradiation Facility ’ DEMO Oriented Neutron Source) will be an installation located in the south of Spain at Granada. Its objective is the fusion material testing by the generation of a neutron flux with a broad energy distribution covering the typical neutron spectrum of a (D-T) fusion reactor. This is achieved by the Li(d, xn) nuclear reactions occurring in a liquid lithium target where a 40 MeV at 125 mA deuteron beam with a variable rectangular beam footprint between 100mm x 50mm and 200mm x 50mm collides. The accelerator system is in charge of providing such high energy deuterons in order to produce the required neutron flux. The High Energy Beam Transport line is the last subsystem of the IFMIF-DONES accelerator and its main functions are to guide the deuteron beam towards the liquid lithium target and to shape it with the required rectangular reference beam footprint. The present work details the status of the HEBT engineering design, including beam dynamics, vacuum configuration, radioprotection, beam diagnostics devices and remote handling analyses performed detailing the layout and integration.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST035
About •	Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 14 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST039	SPS Beam Dump System (SBDS) Commissioning After Relocation and Upgrade	kicker, MMI, controls, hardware	2530
	P. Van Trappen, E. Carlier, L. Ducimetière, V. Namora, V. Senaj, F.M. Velotti, N. Voumard CERN, Meyrin, Switzerland
	In order to overcome several machine limitations, the SBDS has been relocated from LSS1 (Long Straight Section 1) to LSS5 during LS2 (Long Shutdown 2) with an important upgrade of the extraction kicker installation. An additional vertical deflection kicker magnet (MKDV) was produced and installed while the high voltage (HV) pulse generators have been upgraded by changing gas-discharge switches (thyratrons and ignitrons) to semiconductor stacks operating in oil. Furthermore the horizontal sweep generators have been upgraded to allow for a lower kick strengths. The controls, previously consolidated during LS1, went through an additional light consolidation phase with among others the upgrade of the trigger & retrigger distribution system and the installation of a new fast-interlocks detection system. This paper describes the commissioning without and with beam and elaborates on the measured improvements and encountered problems with corrective mitigations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST039
About •	Received ※ 07 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT004	Design of a Compact 180-Degree Single-Shot Energy Spectrometer Based on a Halbach Dipole Magnet	electron, dipole, simulation, detector	2564
	R. Bazrafshan, T. Rohwer Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany M. Fakhari, N.H. Matlis CFEL, Hamburg, Germany F.X. Kaernter DESY, Hamburg, Germany
	In the AXSIS project at DESY, we develop compact THz accelerating structures for a table-top x-ray source. Acceleration is achieved by passing the electron beam through a dielectric-loaded waveguide powered by multi-cycle THz radiation. The final electron energy strongly depends on THz-power injected into the LINAC and timing. Thus in first experiments we expect large energy fluctuations and a large range of energies to cover. We designed an electron energy spectrometer for a wide range of final energies covering 5 to 20 MeV in a single-shot. Here, we present the design of an energy spectrometer which uses a compact dipole magnet based on the Halbach array concept to deflect the electron beam through a 180° path intercepted by a Fiber Optic Scintillator (FOS) mounted inside the vacuum perpendicular to the beam. The 180-degree bending geometry provides the possibility of having the focus point of all energies at the same distance from the magnet edge which makes the design simpler and more compact. It also removes the necessity of installing a safety dipole at the end of the accelerator. A slit system at the spectrometer entrance increases resolution to better than 0.2%.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT004
About •	Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT008	Beam Orbit Shift Due to BPM Thermal Deformation Using Machine Learning	network, storage-ring, synchrotron, feedback	2577
	K.M. Chen, M. Hosaka, F.Y. Wang, G. Wang, Z. Wang, W. Xu USTC/NSRL, Hefei, Anhui, People’s Republic of China L. Guo Nagoya University, Nagoya, Japan
	Stabilizing beam orbit is critical for advanced synchrotron radiation light sources. The beam orbit can be affected by many sources. To maintain a good orbit stability, global orbit feedback systems (OFB) has been widely used. However, the BPM thermal deformation would lead to BPM misreading, which can not be handled by OFB. Usually, extra diagnostics, such as position transducers, is needed to measure the deformation dependency of BPM readings. Here, an alternative approach by using the machine operation historic data, including BPM temperature, insertion device (ID) gaps and corrector currents, is presented. It is demonstrated at Hefei Light Source (HLS). The average orbit shift due to BPM thermal deformation is about 34.5 microns/degree Celsius (horizontal) and 20.0 microns/degree Celsius (vertical).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT008
About •	Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 19 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT022	Study on QE Evolution of Cs₂Te Photocathodes in ELBE SRF Gun-II	cathode, gun, SRF, operation	2617
	R. Xiang, A. Arnold, S. Ma, P. Michel, P. Murcek, A.A. Ryzhov, J. Schaber, J. Teichert, P.Z. Zwartek HZDR, Dresden, Germany
	The quality of the photocathodes is critical for the sta-bility and reliability of the photoinjector’s operation. Thanks to the robust magnesium and Cs₂Te photocathodes, SRF gun-II at HZDR has been proven to be a suc-cessful example in CW mode for high current user operation. In this contribution, we will present our observation of the QE evolution of Cs₂Te photocathodes during SRF gun operation. The variables including substrate surface, film thickness, Cs/Te stoichiometric, multipacting, RF loading and charge extract are considered in the analysis.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT022
About •	Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 06 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT032	SUNDAE2 at EuXFEL: A Test Stand to Characterize the Magnetic Field of Superconducting Undulators	undulator, FEL, laser, experiment	2649
	J.E. Baader, S. Abeghyan, S. Casalbuoni, D. La Civita, B. Marchetti, M. Yakopov, P. Ziolkowski EuXFEL, Schenefeld, Germany H.-J. Eckoldt, A. Hauberg, S. Lederer, L. Lilje, T. Wohlenberg, R. Zimmermann DESY, Hamburg, Germany A.W. Grau KIT, Eggenstein-Leopoldshafen, Germany
	European XFEL foresees a superconducting undulator (SCU) afterburner in the SASE2 hard X-ray beamline. It consists of six 5m-long undulator modules with a 5mm vacuum gap, where each module contains two 2m-long coils and one phase shifter. Prior to installation, the magnetic field must be mapped appropriately. Two magnetic measurement test stands named SUNDAE 1 and 2 (Superconducting UNDulAtor Experiment) are being developed at European XFEL. While SUNDAE1 will be a vertical test stand to measure SCU coils up to two meters with Hall probes in a liquid or superfluid helium bath, SUNDAE2 will measure the SCU coils assembled in the final cryostat. This contribution presents the development status of SUNDAE2 and its main requirements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT032
About •	Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT033	Performance Characterisation at Daresbury Laboratory of Cs-Te Photocathodes Grown at CERN	cathode, electron, emittance, cryogenics	2653
	L.A.J. Soomary, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom C. Benjamin, H.M. Churn, L.B. Jones, T.C.Q. Noakes STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom C. Benjamin University of Warwick, Coventry, United Kingdom E. Chevallay, V.N. Fedosseev, E. Granados, M. Himmerlich, H. Panuganti CERN, Meyrin, Switzerland L.B. Jones, T.C.Q. Noakes, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: STFC Doctoral Training Studentship The search for high-performance photocathodes is a priority in the field of particle accelerators. The surface characteristics of a photocathode affect many important factors of the photoemission process including the photoemission threshold, the intrinsic emittance and the quantum efficiency. These factors in turn define the electron beam quality, which is measurable using figures of merit like beam emittance, brightness and energy spread. We present characterisation measurements for four caesium telluride photocathodes synthesized at CERN. The photocathodes were transported under ultra-high vacuum (UHV) and analysed at STFC Daresbury Laboratory, using ASTeC’s Multiprobe (SAPI)* for surface characterisation via XPS and STM, and for Mean Transverse Energy (MTE) measurements using the Transverse Energy Spread Spectrometer (TESS)*. The MTE measurements were estimated at cryogenic and room temperatures based on the respective transverse energy distribution curves. We discuss correlations found between the synthesis parameters, and the measured surface characteristics and MTE values. B.L. Militsyn, 4-th EuCARD2 WP12.5 meeting, Warsaw, 14-15 March 2017 **L.B. Jones et al., Proc. FEL ’13, TUPPS033, 290-293; https://accelconf.web.cern.ch/FEL2013/papers/tupso33.pdf
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT033
About •	Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT037	Ceramics Evaluation for MW-Power Coaxial Windows, Operating in UHF Frequency Range	Windows, electron, multipactoring, cavity	2668
	S.V. Kutsaev, R.B. Agustsson, P.R. Carriere, N.G. Matavalam, A.Yu. Smirnov, S.U. Thielk RadiaBeam, Santa Monica, California, USA A.A. Haase SLAC, Menlo Park, California, USA T.W. Hall, D. Kim, J.T.M. Lyles, K.E. Nichols LANL, Los Alamos, New Mexico, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Basic Energy Science, under SBIR grant DE- SC0021552 Modern accelerator facilities require reliable high-power RF components. The RF vacuum window is a critical part of the waveguide couplers to the accelerating cavities. It is the point where the RF feed crosses the vacuum boundary and thus forms part of the confinement barrier. RF windows must be designed to have low power dissipation inside their ceramic, be resistant to mechanical stresses, and free of discharges. In this paper, we report on the evaluation of three different ceramic candidates for high power RF windows. These materials have low loss tangents, low secondary electron yield (SEY), and large thermal expansion coefficients. The acquired materials were inspected, coated, and measured to select the optimal set.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT037
About •	Received ※ 01 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 04 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT047	A Double Dipole Kicker for Off and On-Axis Injection for ALBA-II	kicker, injection, dipole, storage-ring	2701
	G. Benedetti, M. Carlà, M. Pont ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
	Injection into the ALBA-II storage ring will be performed off-axis in a 4 meters straight section with a single multipole kicker. We present a novel topology for the coils of the injection kicker, named double dipole kicker (DDK). The resulting magnetic field is the superposition of two opposite dipoles, generated by four inner and four outer conductor rods. When the eight rods are powered, the dipole term cancels and the remaining multipole field is used for off-axis injection. Alternatively, when the four inner rods are switched off, an almost pure dipole is produced, that is useful for on-axis injection during the commissioning. A prototype of DDK is presently under design to be installed and tested in the existing ALBA storage ring. The positioning of the rods is calculated in order to maximise the kick efficiency in mrad/kA and minimise the disturbance to the orbit and the emittance of the stored beam. A metallic coating with optimised thickness along the inner ceramic vacuum chamber should provide compensation for the eddy currents induced field in order to minimize the disturbance to the stored beam while ensuring sufficiently low heat dissipation by the beam image currents.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT047
About •	Received ※ 16 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 20 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT050	Development and Construction of Cryogenic Permanent Magnet Undulators for ESRF-EBS	undulator, SRF, permanent-magnet, cryogenics	2712
	C. Benabderrahmane, P. Brumund, J. Chavanne, D. Coulon, G. Le Bec, B. Ogier, R. Versteegen ESRF, Grenoble, France
	The ESRF Extremely Brilliant Source (ESRF-EBS) is on operation for Users since August 2020 after 20 months of shutdown. This first of a kind fourth generation high energy synchrotron is based on a Hybrid Multi-Bend Achromat lattice. The main goal of the ESRF-EBS is to reduce the horizontal emittance, which leads to a signifi-cant increase of the X-ray source brilliance. To cover the intensive demand of short period small gap undulators at ESRF-EBS, a new design for a 2 m Cryogenic Permanent Magnet Undulator (CPMU) has been developed. Six CPMUs will be installed in the next years; the first two CPMUs have been constructed and actually used on ID15 and ID16 beamline, the third one is under con-structing. An intensive refurbishment work has been done on the existing insertion devices to adapt them to the new accelerator which has shorter straight section and closer dipoles to the IDs than in the old one. This contribution will review the development, construc-tion and commissioning of the new CPMUs, and the refurbishment work done on the existing ones to adapt them to the new accelerator.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT050
About •	Received ※ 02 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT052	The Status of the In-Vacuum-APPLE II Undulator IVUE32 at HZB / BESSY II	undulator, shielding, photon, polarization	2716
	J. Bahrdt, J. Bakos, S. Gaebel, S. Gottschlich, S. Grimmer, S. Knaack, C. Kuhn, F. Laube, A. Meseck, C. Rethfeldt, E.C.M. Rial, A. Rogosch-Opolka, M. Scheer, P.I. Volz HZB, Berlin, Germany
	At BESSY II, two new beamlines for RIXS and for X-Ray-microscopy demand a short period variably polarizing undulator. For this purpose, the first in-vacuum APPLE undulator worldwide is under construction. The parameters are as follows: period length=32mm, magnetic length=2500mm, minimum gap=7mm. The design incorporates a force compensation scheme as proposed by two of the authors at the SRI2018. All precision parts of the drive chain are located in air. New transverse slides for the transversal slit adjustment have been developed and tested. Optical micrometers measure the gap and shift positions, similar to the system of the CPMU17 at BESSY II. They provide the signals for motor feedback loops. A new UHV-compatible soldering technique, as developed with industry, relaxes fabrication tolerances of magnets and magnet holders and simplifies the magnet assembly. A 10-period prototype has been setup for lifetime tests of the new magnetic keeper design. The paper describes first results of the prototype and other key-components and summarizes the status of the full-scale undulator.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT052
About •	Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 22 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT053	Goubau-Line Set Up for Bench Testing Impedance of IVU32 Components	impedance, simulation, undulator, cavity	2719
	P.I. Volz, A. Meseck HZB, Berlin, Germany A. Meseck KPH, Mainz, Germany
	The worldwide first in-vacuum elliptical undulator, IVUE32, is being developed at Helmholtz-Zentrum Berlin. The 2.5 m long device with a period length of 3.2 cm and a minimum gap of about 7 mm is to be installed in the BESSY II storage ring. It will deliver radiation in the soft X-ray range to several beamlines. The proximity of the undulator structure to the electron beam makes the device susceptible to wakefield effects which can influence beam stability. A complete understanding of its impedance characteristics is required prior to installation and operation, as unforeseen heating of components could have catastrophic consequences. To understand and measure the IVU’s impedance characteristics a Goubau-Line test stand is being designed. A Goubau-line is a single wire transmission line for high frequency surface waves with a transverse electric field resembling that of a charged particle beam out to a certain radial distance. A concept optimized for bench testing IVUE32-components will be discussed, microwave simulations will be presented together with first measurements from a test stand prototype.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT053
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK027	Temperature Dependent Effects on Quality Factor in C-band RF Cavities	cavity, cryogenics, shielding, electron	2826
	J.R. Parsons, A. Fukasawa, G.E. Lawler, N. Majernik, J.B. Rosenzweig UCLA, Los Angeles, California, USA
	Funding: This work was supported by DOE Contract DE-SC0020409 Cryogenic operation and associated skin effects are encouraging fields of study for increasing RF gradients of beams within cavities and decreasing the required size for linear accelerators such as free electron lasers. Notably, a cavity’s RF quality factor Q, the ratio of the outgoing RF signal power to the input power, is theoretically multiplied by over 4 when subjected to cryogenic temperatures. Precise measurements of this Q factor require defining a cryostat unit, which consists of a high vacuum chamber, a coldhead, and MLI shielding. We optimized the cryostat by running several cool down tests at high vacuum, incorporating different geometries of MLI shielding to achieve the lowest possible temperatures. We then performed a low power C-band test after installing a cylindrical copper RF cavity to measure the Q factor. Finally, we improved stability and amplification within the chamber by installing edge welded bellows to the coldhead to reduce vibrations. These measurements provide a basis for the development of cryogenic infrastructure to sustain a cryogenic temperature environment for future RF applications.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK027
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK032	A Vacuum System for the Milliampere Booster	cavity, simulation, linac, experiment	2833
	R.G. Heine, C.L. Lorey KPH, Mainz, Germany
	The Milliampere Booster (MAMBO) is the injector linac for the Mainz Energy-recovering Superconducting Accelerator MESA. MESA is a multi-turn energy recovery linac with beam energies in the 100 MeV regime currently designed and built at Institut für Kernphysik (KPH) of Johannes Gutenberg-Universität Mainz. The main accelerator consists of two superconducting Rossendorf type modules, while the injector MAMBO relies on normal conducting technolgy. The MAMBO RF cavities are bi-periodic pi/2 structures that are about 2m long, each. In this paper we present the results of Molflow+ simulations of several setups of the vacuum system for MAMBO that differ in number of pumps, pumping speed and diameter of the pumping ports that are connected to the DN40 beam pipe.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK032
About •	Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK034	Vacuum System Performance of the 3 GeV Electron Storage Ring at MAX IV Laboratory	storage-ring, operation, MMI, injection	2836
	M.J. Grabski, E. Al-Dmour, S.M. Scolari MAX IV Laboratory, Lund University, Lund, Sweden
	The 3 GeV electron storage ring at MAX IV laboratory is the first synchrotron light source with compact multi-bend achromat (MBA) magnet lattice to achieve ultra-low emittance. The vacuum system of the accelerator is fully coated with non-evaporable getter (NEG) thin film to ensure low gas density. The storage ring started commissioning in August 2015 and currently delivers photon beams from insertion devices (IDs) to 9 beamlines that are in user operation or commissioning. After over 6 years of operation, the NEG coated vacuum system continues to be reliable, is conditioning well and do not pose any limitation to the accelerator operation. The average dynamic pressure is lower than the design value (below 3·10^-10 mbar) and is reducing with the accumulated beam dose. The vacuum beam lifetime is greater than 39 Ah, and the total beam lifetime is above the design value of 5 Ah - thus is not limited by the residual gas density. Several successful interventions to install new vacuum components were performed on few achromats in the storage ring during shutdowns. Some of them were done utilizing purified neon gas to vent the vacuum system, thus avoiding the need of re-activation of the NEG coating and saving intervention time without compromising the storage ring performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK034
About •	Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK035	Thermo-Mechanical Modeling and Thermal Performance Analysis of Beam Vacuum Line Interconnections and Cold Warm Transitions in HL-LHC Long Straight Section Magnets	cryogenics, luminosity, radiation, insertion	2839
	J. Harray, C. Garion, V. Petit CERN, Meyrin, Switzerland
	The HL-LHC upgrade, aiming at increasing the LHC levelled luminosity by factor of five, relies on new superconducting magnets requiring a new beam vacuum system. Along with the challenges related to magnet design, the beam optic configuration exposes this new equipment to stringent conditions for vacuum and cryogenic performance. Both cold-warm transitions and magnet interconnections appear to be delicate components that are crucial for the thermal heat transfer between diverse subsystems. The proposed study aims at assessing the heat loads to the cryogenic system and the temperature fields in the vacuum system. A nonlinear static thermal analysis is first performed. A thermo-mechanical approach is developed to capture additional thermal resistance arising from contact between components and their behaviour during cool-down. The system is then studied under dynamic operations when beams are circulating and colliding. A thorough analysis of beam-induced heat loads under ultimate conditions highlights the different relevant contributions. Finally, the transient response of the systems is computed to assess thermal time constants.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK035
About •	Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 29 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK036	Determination of Pumping and Dynamic Vacuum Properties of Conductive Quaternary Alloy of TiZrVAg Non-Evaporable Getter.	photon, electron, experiment, site	2843
	R. Valizadeh, A.N. Hannah, O.B. Malyshev STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom G.Y. Hsiung NSRRC, Hsinchu, Taiwan J.M. O’Callaghan Castella Universitat Politécnica de Catalunya, Barcelona, Spain M. Pont, N.D. Tagdulang ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
	Non Evaporable Getter (NEG) coating has been employed extensively in the particle accelerator especially where the vacuum conductance of the vessel is severely restricted and ultra-high vacuum condition is required. NEG coating will significantly reduce the outgassing rate and provides active pumping surface for H₂, CO and CO₂. In addition, it has been proven that NEG coated surfaces have a very low secondary electron yield, as well as low photon and electron stimulated desorption yields. However, the existing NEG film increases the RF surface resistance of the beam pipe. In order to increase NEG coating conductivity, at ASTeC, in the past several years, the alternative NEG com-position have been studied by adding more conductive element such as Cu, Au, Al and Ag. In this study, we report on the photon stimulated desorption, activation temperature and surface resistance from room temperature to cryogenic temperature for a new NEG quaternary alloy of TiVZrAg as function of the film composition.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK036
About •	Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK037	Measurement of the Photon Stimulated Desorption for Various Vacuum Tubes at a Beam Line of TLS	photon, experiment, radiation, synchrotron	2847
	G.Y. Hsiung, C.M. Cheng NSRRC, Hsinchu, Taiwan R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	For most light sources, the synchrotron radiation (SR) hit on the beam ducts or absorbers results in higher pressure rise and the consequent higher radiation level through the commissioning stage. Various surface treatments, e.g. chemical cleaning, oil-free machining, NEG-coating, etc., for the beam ducts or absorbers have been developed worldwide for mitigating the yield of Photon Stimulated Desorption (PSD). A beam line, BL19B, of 1.5 GeV Taiwan Light Source (TLS) has been modified to measure the PSD-yield of the vacuum tubes. The white light of BL19B covers the critical length at 2.14 keV is suitable for generating higher yield of the photo-electrons (PEY) and the consequent PSD-yield to be measured can be resolved wide range of 10^-2 ~ 10^-7 molecules/photon. The PSD-outgas, measured by RGA, contains the typical H₂, CO, CO₂, hydrocarbons, and Kr from NEG-coating, alcohol from ethanol machined surface, in some cases. The effect of beam-cleaning reflects the PSD-molecules generated from the SR-irradiated surface. The comparison of the PSD for the various vacuum tubes will be described in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK037
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK038	Electron Stimulated Desorption From Titanium Tube	electron, radiation, photon, experiment	2850
	O.B. Malyshev, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Titanium is one of material that used for production of accelerator vacuum chamber and components. In this paper we report the results of vacuum properties evaluation measurements of titanium vacuum chamber. The sample was produced from 40-mm inner diameter tube made of titanium and equipped with CF40 flanges at both ends. The electron stimulated desorption (ESD) was measured after 24-h bakeout to 80, 150, 180 and 250 oC. H₂ and CO initial sticking probabilities were measured after bakeout before the ESD measurements. After ESD measurements, the initial H₂ and CO sticking probabilities were measured again together with CO sorption capacity. These measurements provide the results for ESD as a function of electron dose baked to different temperatures and demonstrate the efficiency of electron stimulated activation of titanium vacuum chamber.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK038
About •	Received ※ 25 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK039	The Effect of Activation Duration on the Performance of Non-Evaporable Getter Coatings	injection, ECR, experiment, target	2854
	E.A. Marshall, O.B. Malyshev, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Non-evaporable getter (NEG) coatings can be activated at temperatures as low as 140°C. However, better pumping properties are achieved using higher temperatures, between 150-300 °C. This paper investigates whether using an increased activation duration can improve the NEG properties obtained using lower activation temperatures, and so decrease the energy and temperature requirement. This could allow a greater range of materials to be used in particle accelerator systems. Our findings have shown that increasing activation duration from 24 hrs to 1 week at 160 °C produces an improvement in the NEG pumping properties.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK039
About •	Received ※ 01 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK040	Few-Nanosecond Stripline Kickers for Top-Up Injection into PETRA IV	kicker, injection, feedback, synchrotron	2858
	G. Loisch, V. Belokurov, F. Obier DESY, Hamburg, Germany
	PETRA IV is the planned ultralow-emittance upgrade of the PETRA III synchrotron light source at DESY, Hamburg. The current baseline injection scheme is an off-axis, top-up injection with few-nanosecond stripline kickers, which would allow for accumulation and least disturbance of experiments during injection. Besides the requirements on kick-strength, field quality, pulse rise-rate, and heat management, two mechanical designs with different apertures are necessary, as the devices will be used for injection and the transverse multi-bunch feedback system. In this contribution we will present the current status of 3D finite element simulations of electromagnetic fields and heating as well as the mechanical design and first pulse electronics tests.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK040
About •	Received ※ 20 May 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 29 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS016	A New Design of PET Cyclotron	cyclotron, proton, acceleration, cavity	2977
	O. Karamyshev JINR, Dubna, Moscow Region, Russia
	An innovative approach to a design of cyclotron allows to produce cheaper and more power efficient cyclotrons for medical and industrial application. 15 MeV cyclotron for PET (and other) isotopes production are widely used and in very high demand. In this paper a design of a very compact and cheap to build and to run cyclotron is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS016
About •	Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS036	HERACLES: A High Average Current Electron Beamline for Lifetime Testing of Novel Photocathodes	cathode, gun, electron, laser	3041
	M.B. Andorf, J. Bae, A.C. Bartnik, I.V. Bazarov, J.M. Maxson Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA L. Cultrera BNL, Upton, New York, USA
	Funding: DOE-NP DE-SC0021425 NSF PHY 1549132 We report on the building and commissioning of a high current beamline dedicated to testing novel photocathodes for high current and spin-polarized electron applications. The main features of the beamline are a 200 keV DC electron gun and a beam dump capable of handling 75 kW of beam power. In this report, a Cs3Sb photocathode is used to demonstrate the facilities high current capabilities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS036
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS053	Proton Beam Irradiation System for Space Part Test	proton, radiation, simulation, target	3093
	H.-J. Kwon, J.J. Dang, W.-H. Jung, H.S. Kim, K.Y. Kim, K.R. Kim, S. Lee, Y.G. Song, S.P. Yun KOMAC, KAERI, Gyeongju, Republic of Korea
	Funding: This work is supported by the Nuclear Research and Development Program (2021M2D1A1045615) through the National Research Foundation of Korea. A proton beam irradiation system for space part test has been developed at Korea Multi-purpose Accelerator Complex (KOMAC) based on 100 MeV proton linac. It consists of a thermal vacuum chamber, a beam diagnostic system and a control system in the low flux beam target room. The thermal vacuum chamber accommodates the capacity for proton beam irradiation in addition to temperature control in vacuum condition. The beam diagnostic system is newly installed to measure the lower dose rate than existing one. In this paper, the proton beam irradiation system for space part test including a thermal vacuum chamber, newly installed beam diagnostic system is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS053
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS055	Commissioning of the SOCHI Applied Station Beam and Beam Transfer Line at the NICA Accelerator Complex	controls, detector, radiation, booster	3099
	A. Slivin, A. Agapov, A.A. Baldin, A.V. Butenko, D.E. Donets, G.A. Filatov, A.R. Galimov, K.N. Shipulin, E. Syresin, A. Tuzikov, V.I. Tyulkin JINR, Dubna, Moscow Region, Russia D.V. Bobrovskiy, A.I. Chumakov, S. Soloviev MEPhI, Moscow, Russia I.L. Glebov, V.A. Luzanov GIRO-PROM, Dubna, Moscow Region, Russia A.S. Kubankin LPI, Moscow, Russia A.S. Kubankin BelSU, Belgorod, Russia T. Kulevoy, Y.E. Titarenko ITEP, Moscow, Russia A.M. Tikhomirov JINR/VBLHEP, Dubna, Moscow region, Russia
	The SOCHI (Station of CHip Irradiation) station was constructed at the NICA accelerator complex for single event effect testing of decapsulated microchips with low-energy ion beams (3.2 MeV/n). The peculiarity of microchip radiation tests in SOCHI is connected with the pulse beam operation of the heavy ion linear accelerator (HILAc) and a restriction on the pulse dose on the target. The SOCHI station construction, the equipment and the results of the first beam runs are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS055
About •	Received ※ 26 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROXSP3	First Operation of a Klystron Fitted with a Superconducting MgB₂ Solenoid	klystron, solenoid, operation, superconductivity	3138
	N. Catalán Lasheras, M. Boronat, G. McMonagle, I. Syratchev CERN, Meyrin, Switzerland A. Baig, A. Castilla Cockcroft Institute, Lancaster University, Lancaster, United Kingdom T. Kimura, P.E. Kolda CPI, Palo Alto, California, USA S. Michizono, A. Yamamoto KEK, Ibaraki, Japan
	As part of the effort to reduce the energy consumption of large research facilities using accelerators, high efficiency klystrons are being developed by CERN. However, a large fraction of the wall-plug power required to operate these klystrons is used in the focusing magnetic elements around the klystron in the form of normal conducting solenoids. In 2019, a prototype solenoid made of MgB₂ was manufactured as a joint venture from CERN, Hitachi and KEK with the aim of reducing the power consumption by a factor ten using higher temperature superconductors. The characteristics of the magnet were measured upon manufacture and checked after the transport across the world. In 2020, the MgB₂ magnet was integrated around one of the klystrons in the X-band facility at CERN and put into operation in the beginning of 2021. We present in this paper the final performance of the klystron when fitted with the new SC solenoid and compare it with the standard normal conducting solenoid system.
	Slides FROXSP3 [4.661 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXSP3
About •	Received ※ 11 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022

Paper

Title

Other Keywords

Page

MOPOST006

Beam Commissioning and Optimisation in the CERN Proton Synchrotron After the Upgrade of the LHC Injectors

MMI, proton, operation, synchrotron

54

A. Huschauer, M.R. Coly, D.G. Cotte, H. Damerau, M. Delrieux, J.-C. Dumont, Y. Dutheil, S.E.R. Easton, M.A. Fraser, O. Hans, G.I. Imesch, S. Joly, A. Lasheen, C.L. Lombard, R. Maillet, B. Mikulec, J.-M. Nonglaton, S. Sainz Perez, B. Salvant, R. Suykerbuyk, F. Tecker, R. Valera Teruel
CERN, Meyrin, Switzerland

The CERN LHC injector chain underwent a major upgrade during the Long Shutdown 2 (LS2) in the framework of the LHC Injectors Upgrade (LIU) project. After 2 years of installation work, the Proton Synchrotron (PS) was restarted in 2021 with the goal to achieve pre-LS2 beam quality by the end of 2021. This contribution details the main beam commissioning milestones, encountered difficulties and lessons learned. The status of the fixed-target and LHC beams will be given and improvements in terms of performance, controls and tools described.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST006

About •

Received ※ 01 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 02 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST011

CEA Contribution to the PIP-II Linear Accelerator

cryomodule, cavity, SRF, linac

74

N. Bazin, J. Belorgey, S. Berry, J. Drant, O. Napoly, A. Raut, P. Sahuquet, C. Simon
CEA-DRF-IRFU, France
S. Arsenyev, Q. Bertrand, P. Brédy, E. Cenni, C. Cloué, R. Cubizolles, H. Jenhani, S. Ladegaillerie, A. Le Baut, A. Moreau, O. Piquet
CEA-IRFU, Gif-sur-Yvette, France
O. Napoly
Fermilab, Batavia, Illinois, USA

The Proton Improvement Plan II (PIP-II) that will be installed at Fermilab is the first U.S. accelerator project that will have significant contributions from international partners. CEA joined the international collaboration in 2018, and will deliver 10 low-beta cryomodules as In-Kind Contribution to the PIP-II project, with cavities supplied by LASA-INFN and power couplers and tuning systems supplied by Fermilab. This paper presents the CEA scope of work that includes the design, manufacturing, assembly and tests of the cryomodules and the upgrade of the existing infrastructures to the PIP-II requirements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST011

About •

Received ※ 13 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST014

The 325 MHz FAIR pLinac Ladder RFQ - Final Assembly for Commissioning

rfq, linac, proton, coupling

82

M. Schuett, U. Ratzinger
IAP, Frankfurt am Main, Germany
C.M. Kleffner, K. Knie
GSI, Darmstadt, Germany

Based on the positive results of the unmodulated 325 MHz Ladder-RFQ prototype from 2013 to 2016, we developed and designed a modulated 3.4 m Ladder-RFQ*. The Ladder-RFQ features a very constant voltage along the axis as well as low dipole modes. The unmodulated prototype accepted 3 times the operating power of which is needed in operation** corresponding to a Kilpatrick factor of 3.1 with a pulse length of 200 µs. The 325 MHz RFQ is designed to accelerate protons from 95 keV to 3.0 MeV according to the design parameters of the proton linac within the FAIR project***. This particular high frequency for a 4-ROD-RFQ creates difficulties, which triggered the development of a Ladder-RFQ with its high symmetry. The results of the unmodulated prototype have shown, that the Ladder-RFQ is very well suited for that frequency. For the applied cooling concept, the Ladder-RFQ can be driven up to a duty factor of 10%. Manufacturing has been completed in September 2018. The final flatness & frequency tuning as well as the final assembly have been completed. We present the final RF measurements and assembly steps getting the Ladder-RFQ ready for shipment and high power RF test prior to assembly.
*Journal of Physics: Conf. Series 874 (2017) 012048
**Proceedings of LINAC2016, East Lansing, TUPLR053
***Proceedings of LINAC20118, pp.787-789

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST014

About •

Received ※ 12 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST022

Upgrade of the Radio Frequency Quadrupole of the ReAccelerator at NSCL/FRIB

rfq, operation, MMI, RF-structure

104

A.S. Plastun, J. Brandon, A.I. Henriques, S.H. Kim, D.G. Morris, S. Nash, P.N. Ostroumov, A.C.C. Villari, Q. Zhao, S. Zhao
FRIB, East Lansing, Michigan, USA
D.B. Crisp, D.P. Sanderson
NSCL, East Lansing, Michigan, USA

Funding: Work supported by the National Science Foundation under grant PHY15-65546
The ReA-RFQ is a four-rod room-temperature structure aimed to be the first step acceleration of rare isotopes as well as stable beams before injection into the ReA SRF linac. The beams of charge to mass ratios of 1/5 to 1/2 from the Electron Beam Ion Trap at 12 keV/u should be accelerated to at least 500 keV/u to be efficiently accelerated in the main SRF linac. Since the commissioning of the original ReA RFQ in 2010 the design voltage has never been reached, and CW operation was never achieved due to cooling issues. In 2016 a new design including trapezoidal modulation was proposed, which permitted achieving increased reliability, and would allow reaching the original required specifications. The proposed new rods were built and installed in 2019 and commissioned in the same year. Since then, the RFQ has been working very successfully. Recently it was opened for inspection and verification of its internal status. No damage and discoloration were observed. This contribution will describe the RFQ rebuild process, involving specific RF protections and other technical aspects related to the assembly of the structure. Results of the operation with a variety of beams will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST022

About •

Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 11 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST049

Electron Cloud Build-Up for the Arc Sextupole Sections of the FCC-ee

electron, collider, simulation, sextupole

191

J.E. Rocha Muñoz, G.H.I. Maury Cuna
Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Mexico
K.B. Cantún-Ávila
UADY, Mérida, Yucatán, Mexico
F. Zimmermann
CERN, Meyrin, Switzerland

Funding: Consejo Nacional de Ciencia y Tecnología (CONACyT) - México
In particle accelerators that operate with positrons, an electron cloud may occur due to several mechanisms. This work reports preliminary studies on electron cloud build-up for the arc sextupole sections of the positron ring of the FCCe⁺e⁻ using the code PyECLOUD. We compute the electron cloud evolution while varying strategic parameters and consider three simulation scenarios. We report the values of the central density just before the bunch passage, which is related to the single-bunch instability threshold and the electron density threshold for the three scenarios. In addition, we compare the simulated electron distribution across the central circular cross-section for a chamber with and without winglets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST049

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT018

Advancing to a GHz Transition Radiation Monitor for Longitudinal Charge Distribution Measurements

radiation, target, simulation, electron

267

S. Klaproth, A. Penirschke
THM, Friedberg, Germany
H. De Gersem
TEMF, TU Darmstadt, Darmstadt, Germany
T. Reichert, R. Singh
GSI, Darmstadt, Germany

Funding: This work is supported by the German Federal Ministry of Education and Research (BMBF) under contract no. 05P21RORB2. Joint Project 05P2021 - R&D Accelerator (DIAGNOSE)
In the past, longitudinal beam profiles have been measured with e.g., Feschenko monitors*, Fast Faraday Cups (FFC)** and field monitors. Feschenko monitors usually examine an average shape over several pulses and FFCs are interceptive devices by design. In this work we want to present the progress in the development of a novel GHz diffraction radiation monitor which shall be able to measure the longitudinal charge distribution of single bunches within Hadron beam LINACS non-destructively. A proof-of-concept measurement has been performed at GSI. We aim for a resolution of 50 to 100ps at beam energies of β=0.05 to 0.74. electronic field simulations were performed using CST Particle Studio to determine an optimal RF-Window, which also suits as vacuum chamber and the beam energy and angular dependencies of the diffraction radiation for different materials were analyzed.
* A. V. Feschenko (2001): Methods and Instrumentation for Bunch Shape Measurements. In Proc. PAC’01, paper ROAB002
** G. Zhu et al (2018): Rev. Sci. Instrum. issn 0034-6748, doi :10.1063/1.5027608

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT018

About •

Received ※ 14 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT037

Beam Measurement and Application of the Metal Vapor Vacuum Arc Ion Source at KOMAC

radiation, ion-source, extraction, experiment

328

S.H. Lee, H.S. Kim, H.-J. Kwon
KOMAC, KAERI, Gyeongju, Republic of Korea

Funding: This work has been supported through KOMAC operation fund of KAERI by MSIT (Ministry of Science and ICT) and the NRF (National Research Foundation) of Korea grant fund the Korea government (MSIT).
The metal ion beam facility is developed based on the MEVVA* ion source at the KOMAC**. The MEVVA ion source has advantage that it can be extract almost metal ion species as well as high current ion beam. After the installation, we measured beam properties such as peak beam current, beam profile depending on the operation condition. The average charge state is measured in order to estimate the total dose. We evaluate the beam stability through the long-term beam extraction, and the measured the cathode erosion rate too. In addition, as one of the application fields, we irradiate the metal beam on the cathode of the fuel cell and measured the performance. In this paper, the beam measurement results, are summarized and fuel cell performances after metal beam irradiation are discussed.
*Korea Multi-purpose of Accelerator Complex
**Metal Vapor Vacuum Arc

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT037

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 21 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT048

Design of a Prototype Gas Jet Profile Monitor for Installation Into the Large Hadron Collider at CERN

electron, proton, experiment, photon

363

R. Veness, M. Ady, C. Castro Sequeiro, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski
CERN, Meyrin, Switzerland
P. Forck, S. Udrea
GSI, Darmstadt, Germany
N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom
N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom

The Beam-Gas Curtain or BGC is the baseline instrument for monitoring the concentricity of the LHC proton beam with a hollow electron beam for the hollow e-lens (HEL) beam halo suppression device which is part of the High-Luminosity LHC upgrade. The proof-of-principles experiments of this gas-jet monitor have now been developed into a prototype instrument which has been built for integration into the LHC ring and is now under phased installation for operation in the upcoming LHC run. This paper describes the challenges overcome to produce a gas-jet fluorescence monitor for the ultra-high vacuum accelerator environment. It also presents preliminary results from the installation of the instrument at CERN.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT048

About •

Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT054

A Modified Nomarski Interferometer to Study Supersonic Gas Jet Density Profiles

laser, experiment, optics, diagnostics

385

C. Swain, O. Apsimon, A. Salehilashkajani, C.P. Welsch, J. Wolfenden, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom
Ö. Apsimon, A. Salehilashkajani, C. Swain, C.P. Welsch, J. Wolfenden, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom

Funding: This work is supported by the AWAKE-UK phase II project grant No. ST/T001941/1, the STFC Cockcroft core grant No. ST/G008248/1 and the HL-LHC-UK phase II project funded by STFC under Grant Ref: ST/T001925/1.
Gas jet-based non-invasive beam profile monitors, such as those developed for the high luminosity Large Hadron Collider (HL-LHC) upgrade, require accurate, high resolution methods to characterise the supersonic gas jet density profile. This paper proposes a modified Nomarski interferometer to non-invasively study the behaviour of these jets, with nozzle diameters of 1 mm or less in diameter. It discusses the initial design and results, alongside plans for future improvements. Developing systems such as this which can image on such a small scale allows for improved monitoring of supersonic gas jets used in several areas of accelerator science, thus allowing for improvements in the accuracy of experiments they are utilised in.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT054

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT056

Commissioning of a Gas Jet Beam Profile Monitor for EBTS and LHC

electron, photon, simulation, MMI

393

H.D. Zhang, N. Kumar, A. Salehilashkajani, O. Sedláček, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
M. Ady, T. Lefèvre, S. Mazzoni, I. Papazoglou, A. Rossi, G. Schneider, O. Sedláček, K. Sidorowski, R. Veness
CERN, Meyrin, Switzerland
P. Forck, S. Udrea
GSI, Darmstadt, Germany
N. Kumar, A. Salehilashkajani, O. Sedláček, O. Stringer, C.P. Welsch, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom

Funding: This work is supported by the HL-LHC-UK II project funded by STFC and CERN and the STFC Cockcroft core grant No. ST/G008248/1.
A gas jet beam profile monitor was designed for measuring the electron beam at the electron beam test stand (EBTS) for the Hollow electron lens (HEL) and the proton beam in the large hadron collider (LHC). It is partially installed in the LHC during the second long shutdown. The current monitor is tailored to the accelerator environment including vacuum, geometry, and magnetic field for both the EBTS and the LHC. It features a compact design, a higher gas jet density, and a wider curtain size for a better integration time and a larger detecting range. In this contribution, the commissioning of this monitor at the Cockcroft Institute will be discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT056

About •

Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK043

Wakefield Effects Evaluation on Nanometer Small Beam at KEK-ATF

wakefield, simulation, alignment, cavity

556

Y. Abe, K. Kubo, T. Okugi, N. Terunuma
Sokendai, Ibaraki, Japan
K. Kubo, T. Okugi, N. Terunuma
KEK, Ibaraki, Japan

Funding: This work was supported by JST, the establishment of university fellowships towards the creation of science technology innovation, Grant Number JPMJFS2136. This work was also supported by JST SPRING, Grant Number SDP221102.
Accelerator Test Facility (ATF) is R&D facility to evaluate final focus technology for small beam required by ILC. The final focus beamline(ATF2) sets the goal to achieve 37 nm vertical beam size and 41 nm beam size had been demonstrated. Moreover, a significant intensity dependence on a nanometer beam size was observed and several studies of the wakefield had been conducted [*,**,***]. ATF2 is a proper beamline for wakefield studies with low emittance beam and nanometer resolution cavity BPMs and a nanometer beam size monitor. The simulation results were qualitatively cross-checked with experimental results and showed that the effects of some vacuum components and BPMs were significant. Further analysis of the wakefield will be done for flexible components (e.g. bellows). An upgrade of the ATF2 beamline is proposed by including minimization of the wakefield sources, to establish technologies for stable nanometer beam.
*J.Snuverink et al., PHYS. REV.ACCEL. BEAMS19, 091002.
**T.Okugi et al., PASJ16, FRPI023, 2019.
***P.Korysko et al., PHYS. REV.ACCEL. BEAMS23, 121004.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK043

About •

Received ※ 20 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 01 July 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS004

Optimizing Activation Recipe with Cs, Te, O for GaAs-Based Photocathodes

cathode, electron, site, polarization

628

J. Bae, M.B. Andorf, I.V. Bazarov, A. Galdi, J.M. Maxson
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
L. Cultrera
BNL, Upton, New York, USA

Funding: Department of Energy (DOE) DE-SC0021039.
GaAs-based photocathodes are the most popular electron sources for producing highly spin-polarized electron beams in accelerator physics and condensed matter physics. Spin-polarized photoemission requires activation to achieve Negative Electron Affinity (NEA). Conventional NEA surfaces such as CS-O/NF3 are extremely vacuum sensitive, and this results in rapid QE degradation. In this work, we activated GaAs with various recipes using Cs, Te, and oxygen. We demonstrate NEA activation on GaAs surfaces. Among Cs-Te activated samples, the oxidized sample showed the highest QE and longest lifetime at 780 nm.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS004

About •

Received ※ 04 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS007

Optimized Dielectric Loaded Waveguide Terahertz LINACs

electron, acceleration, linac, GUI

634

M. Vahdani
University of Hamburg, Hamburg, Germany
M. Fakhari
DESY, Hamburg, Germany
F.X. Kärtner
The Hamburg Center for Ultrafast Imaging, University of Hamburg, Hamburg, Germany
F.X. Kärtner
Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
M. Vahdani
CFEL, Hamburg, Germany

Dielectric loaded waveguides (DLW) powered by multicycle terahertz (THz) pulses have shown promising performance as compact linear accelerators due to higher breakdown fields at THz frequencies compared to conventional RF components. By changing the dielectric dimensions one can control phase and group velocities of the THz pulse inside the DLW. Since optimum waveguide dimensions are dependent on initial electron energy, THz pulse energy, and etc., it is worthwhile to determine optimum values for different conditions to maximize final kinetic energy. In this work, we present a combined analytical/numerical guide to determine the optimum DLW parameters for single on-axis electron acceleration. We also introduce normalized graphic representations to visualize optimum designs for different initial electron and THz pulse energies.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS007

About •

Received ※ 09 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS019

The New SPARC_LAB RF Photo-Injector

gun, operation, solenoid, quadrupole

671

D. Alesini, M.P. Anania, M. Bellaveglia, A. Biagioni, F. Cardelli, G. Costa, M. Del Franco, G. Di Pirro, L. Faillace, M. Ferrario, G. Franzini, A. Gallo, A. Giribono, L. Piersanti, L. Sabbatini, A. Stella, A. Vannozzi
INFN/LNF, Frascati, Italy
A. Battisti, E. Chiadroni, G. Di Raddo, A. Liedl, V.L. Lollo, L. Pellegrino, R. Pompili, S. Romeo, V. Shpakov, C. Vaccarezza, F. Villa
LNF-INFN, Frascati, Italy
M. Carillo, E. Chiadroni
Sapienza University of Rome, Rome, Italy
A. Cianchi, M. Galletti
Università di Roma II Tor Vergata, Roma, Italy

A new RF photo-injector has been designed, realized and successfully installed at the SPARC_LAB facility (INFN-LNF, Frascati, Rome). It is based on a 1.6 cell RF gun fabricated with the new brazing free technology recently developed at the National Laboratories of Frascati. The electromagnetic design has been optimized to have a full compensation of the dipole and quadrupole field components introduced by the coupling hole with an improvement of the effective pumping speed with two added pumping ports. The gun is overcoupled (\beta=2) to reduce the filling time and to allow the operation with short RF pulses. The overall injector integrates a new solenoid with a remote control of the transverse position and a variable skew quadrupole for the compensation of residual quadrupole field components. It also allows an on axis laser injection system with the last mirror in air, and the possibility of a future integration of an X/C band cavity linearizer. In the paper we report the main characteristics of the electromagnetic and mechanical design and the low and high power test results that shows the extremely good perfomances of the new device.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS019

About •

Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS034

Material Normal Energy Distribution for Field Emission Analyses From Monocrystalline Surfaces

electron, lattice, framework, cathode

713

J.I. Mann, Y. Li, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
T. Arias, J.K. Nangoi
Cornell University, Ithaca, New York, USA

Funding: National Science Foundation Grant No. PHY-1549132
Electron field emission is a complicated phenomenon which is sensitive not only to the particular material under illumination but also to the specific crystalline orientation of the surface. Summarizing the ability for a crystal to emit in a particular direction would be of great use when searching for good field emitters. In this paper we propose a material normal energy distribution which describes the ability of the bound electrons to tunnel under an intense electric field. This framework breaks a computationally expensive 3-D system down to a source distribution representation applicable for more efficient 1-D models. We use the Fowler-Nordheim framework to study the yield and MTE (mean transverse energy) from sources including gold, copper, and tungsten in both monocrystalline and polycrystalline forms. We find an increase in effective work function for field emission in the (111) direction for gold and copper associated with the Bragg plane intersections of the Fermi surface.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS034

About •

Received ※ 20 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 06 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS036

Simulations of Laser Field Emission from Nanostructures with Image Charge Trapping and Band Structure Transitions

electron, laser, simulation, photon

717

B. Wang, G.E. Lawler, J.I. Mann, J.B. Rosenzweig
UCLA, Los Angeles, California, USA
T. Arias, J.K. Nangoi
Cornell University, Ithaca, New York, USA
S.S. Karkare
Arizona State University, Tempe, USA

Funding: National Science Foundation Grant No. PHY-1549132
Laser-induced field emission from nanostructures as a means to create high brightness electron beams has been a continually growing topic of study. Experiments using nanoblade emitters have achieved peak fields upwards of 40 GV/m, begging further investigation in this extreme regime. A recent paper has provided analytical reductions of the common semi-infinite Jellium system for pulsed incident lasers. We utilize these results as well as similar previous results to further understand the physics underlying electron rescattering-type emissions. We progress in numerically evaluating the analytical solution to attempt to more efficiently generate spectra for this system. Additionally, we use the full 1-D time-dependent Schrödinger equation with a Hartree potential and a dispersion-relation transition from material to vacuum to study the same system. We determine what importance the inclusion of the material band structure may have on emissions using this computationally challenging approach.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS036

About •

Received ※ 08 June 2022 — Revised ※ 21 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 01 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS045

Vacuum Control System Upgrade for ALPI Accelerator

controls, PLC, hardware, EPICS

744

G. Savarese, L. Antoniazzi, D. Bortolato, A. Conte, F. Gelain, D. Marcato, C.R. Roncolato
INFN/LNL, Legnaro (PD), Italy

The vacuum system of ALPI accelerator includes about 40 pumping groups based on turbomolecular pumps. The instrumentation of the accelerators complex is mainly the one installed in 90s, with consequent maintenance issues. The control and supervision systems were developed in the same period by an external company, which produced custom solutions for the HW and SW parts. Control devices are based on custom PLCs, while the supervision system is based on C and C#. The communication between the field and the supervisor is composed of multiple levels: RS-232 standard is used to transfer control parameter from the field devices up to custom multiplexers; RS-485 transmission is used from the multiplexers to two PC servers covering different sections of the installation; while Ethernet, is used to connect the servers and the operation console. Obsolescence and rigidity of the system, deficit of spare parts and impossibility of reparation or modification without external support, required a complete renovation of the vacuum system and relative controls in the next years. This paper describes the adopted strategy and the implementation status.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS045

About •

Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 30 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOMS047

Control and Functional Safety Systems Design for Real-Time Conditioning of RF Structures at TEX

controls, EPICS, interface, framework

751

S. Pioli, R. Gargana, D. Moriggi
LNF-INFN, Frascati, Italy
F. Cardelli, P. Ciuffetti, C. Di Giulio
INFN/LNF, Frascati, Italy

We report the status of the development of an High Power RF Laboratory in X-Band called TEX (TEst-stand for X-Band). TEX is part of the LATINO (Laboratory in Advanced Technologies for INnOvation) initiative that is ongoing at the Frascati National Laboratories (LNF) of the Italian Institute for Nuclear Physics (INFN) that covers many different areas focused on particle accelerator technologies. TEX is a RF test facility based on solid-state K400 modulator from ScandiNova with a 50MW class X-band (11.994 GHz) klystron tube model VKX8311A operating at 50 Hz. This RF source will operate as resource for test and research programs such as the RF breakdown on RF waveguide components as well as high power testing of accelerating structures for future high gradient linear accelerator such as EuPRAXIA and CLIC. In this context we will present the whole EPICS control system design focusing on archiving, user interfaces and custom development made as part of the functional safety to deliver real-time RF breakdown detection integrated with the timing system of the facility.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOMS047

About •

Received ※ 16 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 27 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOOPLGD2

SPS-II: A 4th Generation Synchrotron Light Source in Southeast Asia

storage-ring, synchrotron, lattice, photon

764

P. Klysubun, S. Boonsuya, T. Chanwattana, S. Jummunt, N. Juntong, A. Kwankasem, T. Phimsen, P. Photongkam, S. Prawanta, T. Pulampong, K. Sittisard, S. Srichan, P. Sudmuang, P. Sunwong, O. Utke
SLRI, Nakhon Ratchasima, Thailand

Upon its completion, Siam Photon Source II (SPS-II) will be the first 4th generation synchrotron light source in Southeast Asia. The 3.0 GeV, 327.5 m storage ring based on the Double-Triple Bend Achromat lattice will have the natural emittance of 0.97 nm·rad. The storage ring includes 14 long and 14 short straight sections for insertion devices and machine subsys-tems. The beam injection will be performed by a 150 MeV linear accelerator and a full-energy concentric booster synchrotron sharing the same tunnel with the storage ring. In the first phase, there will be 7 insertion devices and 7 associated beamlines with the end sta-tions for different techniques utilizing synchrotron radiation from 80 eV to 60 keV. High-energy and high-brightness radiation generated by the new light source will serve as one of the most powerful analytical tools in the region for advanced science and technology research.

Slides MOOPLGD2 [4.168 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOOPLGD2

About •

Received ※ 12 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOPT014

The Status of the SASE3 Variable Polarization Project at the European XFEL

undulator, polarization, FEL, radiation

1029

S. Karabekyan, S. Abeghyan, M. Bagha-Shanjani, S. Casalbuoni, U. Englisch, W. Freund, G. Geloni, J. Grünert, S. Hauf, C. Holz, D. La Civita, J. Laksman, D. Mamchyk, M.P. Planas, F. Preisskorn, S. Serkez, H. Sinn, M. Wuenschel, M. Yakopov, C. Youngman
EuXFEL, Schenefeld, Germany
P. Altmann, A. Block, W. Decking, L. Fröhlich, O. Hensler, T. Ladwig, D. Lenz, D. Lipka, R. Mattusch, N. Mildner, E. Negodin, J. Prenting, F. Saretzki, M. Schlösser, F. Schmidt-Föhre, E. Schneidmiller, M. Scholz, D. Thoden, T. Wamsat, T. Wilksen, T. Wohlenberg, M.V. Yurkov
DESY, Hamburg, Germany
J. Bahrdt
HZB, Berlin, Germany
M. Brügger, M. Calvi, S. Danner, R. Ganter, L. Huber, A. Keller, C. Kittel, X. Liang, S. Reiche, M.S. Schmidt, T. Schmidt, K. Zhang
PSI, Villigen PSI, Switzerland
D.E. Kim
PAL, Pohang, Republic of Korea
Y. Li
IHEP, People’s Republic of China

The undulator systems at the European XFEL consist of two hard X-ray systems, SASE1 and SASE2, and one soft X-ray system, SASE3. All three systems are equipped with planar undulators using permanent neodymium magnets. These systems allow the generation of linearly polarized radiation in the horizontal plane. In order to generate variable polarization radiation in the soft X-ray range, an afterburner is currently being implemented behind the SASE3 planar undulator system. It consists of four APPLE-X helical undulators. The project, called SASE 3 Variable Polarization, is close to being put into operation. All four helical undulators have been installed in the tunnel during the 2021-2022 winter shutdown. This paper describes the status of the project and the steps toward its commissioning. It also presents lessons learned during the implementation of the project.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT014

About •

Received ※ 02 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOPT024

Recent Developments at SOLARIS National Synchrotron Radiation Centre

synchrotron, radiation, operation, plasma

1051

A.I. Wawrzyniak, P. Andryszczak, G. Cios, K. Gula, G.W. Kowalski, A.M. Marendziak, A. Maximenko, R. Panaś, T. Sobol, M. Szczepaniak, J.J. Wiechecki, M. Wiśniowski, M. Zając
NSRC SOLARIS, Kraków, Poland
A. Curcio
CLPU, Villamayor, Spain
H. Lichtenberg
Hochschule Niederrhein University of Applied Sciences, Krefeld, Germany

SOLARIS National Synchrotron Radiation Centre is under constant development of the research infrastructure. In 2018 first users were welcomed at three different experimental stations. Up to now 5 end stations are available at SOLARIS for experiments at 4 beamlines, and 4 new beamlines are under construction. In 2021 new front end for POLYX beamline was installed and de-gassed. Moreover, ASTRA beamline components were installed and first commissioning stage has stared. Additionally, a plasma cleaning station has been designed, built and is currently tested. Apart of the beamlines, up-grades to the linac and storage ring operation have been done. During the COVID-19 pandemic the software for remote injection process was developed and is used on daily basis. The transverse beam emittance measurement on the visible light beamline LUMOS was implemented and gives results that are complementary to the Pinhole beamline. Within this presentation the overview of the recent developments with insight to the details to be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOPT024

About •

Received ※ 09 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 21 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK003

High Power RF Conditioning of the ESS RFQ

rfq, cavity, operation, interlocks

1189

O. Piquet, A.C. Chauveau, P. Hamel
CEA-IRFU, Gif-sur-Yvette, France
M. Baudrier, M.J. Desmons
CEA-DRF-IRFU, France
B. Jones, D. Noll, A.G. Sosa, E. Trachanas, R. Zeng
ESS, Lund, Sweden

The 352.21 MHz Radio Frequency Quadrupole (RFQ) for the European Spallation Source ERIC (ESS) has been delivered by the end of 2019 by CEA/IRFU. The RFQ is designed to accelerate a 70 mA proton beam from 75 keV up to 3.62 MeV. It consists of a 4-vane resonant cavity with a total length of 4.6 m. Two coaxial power loop couplers feed the RFQ with the 1.4 MW of RF power required for beam operation. This paper first presents the main systems required for the RFQ conditioning. Then it summarizes the main steps and results of this high power RF conditioning completed at ESS from June 9 to July 29, 2021 in order to achieve the nominal field for a pulse length of 3.2ms at the repetition rate of 14Hz.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK003

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 09 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK009

Development of Superconducting CH Cavity Preparation at IAP

cavity, simulation, coupling, ECR

1208

P. Müller, H. Podlech
IAP, Frankfurt am Main, Germany
K. Aulenbacher, F.D. Dziuba, V. Gettmann, T. Kürzeder, M. Miski-Oglu
HIM, Mainz, Germany
W.A. Barth, M. Basten, V. Gettmann, T. Kürzeder, M. Miski-Oglu
GSI, Darmstadt, Germany

Funding: HIC for FAIR, BMBF Contr. No. 05P21RFRB2 and HFHF
Goethe University (GU), Gesellschaft für Schwerionenforschung (GSI) and Helmholtz Institut Mainz (HIM) work in collaboration on the Helmholtz Linear Accelerator (HELIAC). A new superconducting (sc) continous wave (cw) high intensity heavy ion linear accelerator (Linac) will provide ion beams with maximum duty factor up to beam energies of 7.3 MeV/u. The acceleration voltage will be provided by sc Crossbar-H-mode (CH) cavities, developed of Institute for Applied Physics (IAP) at GU. Cavity preparation is researched and optimized towards widely used elliptical multicell cavities. A standardized preparation protocol for CH cavities is researched in collaboration between GU, GSI and HIM on a 360 MHz 19 gap CH prototype. Baseline measurements and a 120°C 48 hour bake produced higher maximum gradient, higher intrinsic quality factor and a shorter cavity conditioning phase. As a critical preparation step, High Pressure Rinsing (HPR) with ultra pure water will be performed at HIM and is currently in preparation. HPR cycles are currently tested on a CH dummy with a new nozzle layout that is optimized towards CH cavity geometry.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK009

About •

Received ※ 08 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 02 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK012

Nitrogen Infusion Sample R&D at DESY

cavity, niobium, ECR, accelerating-gradient

1219

C. Bate
University of Hamburg, Hamburg, Germany
A. Ermakov, D. Reschke, J. Schaffran
DESY, Hamburg, Germany
W. Hillert, M. Wenskat
University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany

Funding: This work was supported by the Helmholtz Association within the topic Accelerator Research and Development (ARD) of the Matter and Technologies (MT) Program.
Many accelerator projects such as the ILC would benefit from cavities with reduced surface resistance (high Q-values) while maintaining a high accelerating gradient. A possible way to meet the requirements is the so-called nitrogen-infusion procedure on Niobium cavities. However, a fundamental understanding and a theoretical model of this method are still missing. One important parameter is the residual resistance ratio (RRR) which is related to the impurity content of the material. We report the investigated RRR on samples in a wide temperature range in a vacuum and under a nitrogen atmosphere. This comparison made it possible to make statements about the differences in the concentration of nitrogen by varying the temperature. The samples are pure cavity-grade niobium and treated in the same manner as cavities. For this purpose, a small furnace dedicated to sample treatment was set up to change and explore the parameter space of the infusion recipe. Care was taken to achieve the highest level of purity possible in the furnace and in a pressure range of 1.0·10^-8 mbar in order to meet the high requirements of nitrogen infusion.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK012

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 01 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK018

Combined In-Situ QEXAFS and XRD Investigations on Nb-Treatments in N₂ Gas Atmospheres at Elevated Temperatures

site, cavity, niobium, SRF

1238

P. Rothweiler, F. Eckelt, D. Lützenkirchen-Hecht, S. Paripsa, L. Voß
University of Wuppertal, Wuppertal, Germany

Funding: We gratefully acknowledge financial support by the German Federal Ministry of Education and Research (BMBF) under project No. 05H18PXRB1.
Thin polycrystalline Nb metal foils were treated in N₂ gas atmospheres at elevated temperatures of 900 °C up to 1200 °C. A combination of transmission mode Quick X-ray absorption spectroscopy (QEXAFS) at the Nb-K-edge and X-ray diffraction (XRD) used in parallel were used to investigate changes in the atomic short and long-range structure of the bulk Nb-material in-situ. A dedicated high-vacuum heating cell with a base pressure of 10^-6 mbar was used to perform the heat treatments under vacuum and nitrogen gas atmosphere. The treatments typically included (i) a preheating at 900 °C under high-vacuum, (ii) a treatment in 3 mbar nitrogen gas at the desired temperature and (iii) a cooldown to room temperature under vacuum conditions. The QEXAFS and XRD data were collected in parallel during the entire process with a time resolution of 4 s. While the samples treated at 900 °C show the typical N-uptake to the octahedral interstitial sites, the samples treated at higher temperatures show the growth of distinct niobium nitride phases. The results will be discussed in more details during the conference.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK018

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 18 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK025

Design Study of the Third Harmonic Superconducting Cavity for a Bunch Lengthening

cavity, superconducting-cavity, status, HOM

1258

J.Y. Yoon, E.-S. Kim
KUS, Sejong, Republic of Korea
J.H. Han, H.S. Park
Kiswire Advanced Technology Ltd., Daejeon, Republic of Korea
E. Kako
KEK, Ibaraki, Japan

The bunch lengthening by the 3rd harmonic cavity reduces the electron collisions in a bunch and increases the Touschek lifetime of a storage ring. We performed the multi-physics simulations including the electromagnetic, thermal, and mechanical analysis of the cavity. In the electromagnetic simulation, the geometry is optimized for the required performance of the cavity. The elliptical double-cell geometry is selected to increase the accelerating voltage and reduce the power losses of the cavity. Thermal/mechanical analyses were performed to check the deformation of the thermal and pressure contraction. The prototype cavity does not require the power coupler as it is a passive type. The conceptual design and copper prototype of the 3rd harmonic cavity will be described in this paper. Based on this design, the fabrication of Niobium cavity is in progress.
Superconducting RF, Cavity

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK025

About •

Received ※ 02 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 09 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK026

ESS Elliptical Cryomodules Tests at Lund Test Stand

cavity, cryomodule, operation, LLRF

1261

C.G. Maiano, E. Asensi Conejero, N. Elias, P. Goudket, W. Hees, P. Pierini, L. Sagliano, F. Schlander, M.Y. Wang
ESS, Lund, Sweden
D. Bocian, W. Gaj, P. Halczynski, M. Sienkiewicz, F.D. Skalka, J. Swierblewski, K.M. Wartak, M. Wartak
IFJ-PAN, Kraków, Poland

We present an overview and description of the elliptical cryomodules test activities at Lund Test Stand 2. During 2021 the test facility was commissioned with one prototype, and four series medium beta modules have now been successfully tested at ESS in Lund. This activity allowed the joint ESS and IFJ PAN team to develop all the procedures and the necessary automated tools for the different phases of the site acceptance test campaign (e.g. incoming inspections, coupler conditioning, cooldown strategies, tuning to resonance and electromagnetic/cryogenic performance verification). During the initial test period techniques for diagnostics of limiting mechanisms have been developed and improved up to a consolidated and mature state for the rest of the test campaign. Tests results and the initial statistics is presented and commented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK026

About •

Received ※ 07 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 16 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK042

Challenges to Reliable Production Nitrogen Doping of Nb for SRF Accelerating Cavities

cavity, niobium, SRF, controls

1311

C.E. Reece, M.J. Kelley, E.M. Lechner, A.D. Palczewski
JLab, Newport News, Virginia, USA
J.W. Angle, M.J. Kelley
Virginia Polytechnic Institute and State University, Blacksburg, USA
F.A. Stevie
NCSU AIF, Raleigh, North Carolina, USA

Funding: This work was authored by JSA LLC under U.S. DOE contract DE-AC05-06OR23177. This material is based on work supported by the U.S. DOE Early Career Award to A. Palczewski, with supplemental support from DOE BES via the LCLS-II HE R&D program. J. Angle’s support was from the Office of High Energy Physics, under grant DE-SC-0014475 to Virginia Tech.
Over the last several years, alloying of the surface layer of niobium SRF cavities has been demonstrated to beneficially lower the superconducting RF surface resistance. Nitrogen, titanium, and oxygen have all been demonstrated as effective alloying agents, occupying interstitial sites in the niobium lattice within the RF penetration depth and even deeper, when allowed to thermally diffuse into the surface at appropriate temperatures. The use of nitrogen for this function has been often termed ’nitrogen doping’ and is being applied in the LCLS-II and LCLS-II HE projects. We report characterization studies of the distribution of nitrogen into the exposed niobium surface and how such distribution is affected by the quality of the vacuum furnace environment in which the doping takes place, and the complexity of nitride crystal growth on different grain orientations of surface niobium. Using state-of-the-art quantification methods by dynamic secondary ion mass spectrometry (SIMS) depth profiling in niobium, we identify several phenomena involving furnace-sourced contamination. We also highlight a potential issue with N₂ flow constraints from the flange ’caps’ used during heat treatments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK042

About •

Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK052

Influence of a Positive Grid Biasing on RF System in J-PARC RCS

controls, acceleration, power-supply, operation

1336

M. Yamamoto, M. Nomura, H. Okita, T. Shimada, F. Tamura
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
K. Hara, K. Hasegawa, C. Ohmori, Y. Sugiyama, M. Yoshii
KEK, Tokai, Ibaraki, Japan

In order to accelerate a high intensity beam in the RCS, a large amplitude of the anode current is provided by a tube amplifier to compensate a heavy beam loading. Tetrode vacuum tubes are used in the RCS, and the control grid voltage enters into a positive region to feed such a large current. The positive grid biasing affects the waveform of the control grid voltage; it is deformed due to the induced control grid current under the condition of the multi-harmonic rf driving. Furthermore, the DC bias voltage drop on the control grid is observed because of the exceeding the ability for the control grid power supply. We describe the influence of the positive grid biasing in the RCS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK052

About •

Received ※ 06 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 22 June 2022 — Issue date ※ 24 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOTK059

Modeling O and N Alloying in Nb for SRF Applications

cavity, SRF, niobium, radio-frequency

1354

E.M. Lechner, M.J. Kelley, A.D. Palczewski, C.E. Reece
JLab, Newport News, Virginia, USA
J.W. Angle, M.J. Kelley
Virginia Polytechnic Institute and State University, Blacksburg, USA
F.A. Stevie
NCSU AIF, Raleigh, North Carolina, USA

Funding: This work was coauthored by Jefferson Science Associates LLC under U.S. DOE Contract No. DE-AC05-06OR23177 and grant No. DE-SC-0014475 to Virginia Tech for the support of J. Angle.
N and O-alloyed superconducting radio frequency cavities exhibit extraordinary quality factors. Developing diffusion models that describe interstitial N and O in Nb is important for optimizing alloyed cavity quality factors and accelerating gradients. N and O-alloyed Nb samples are examined with SEM AND SIMS and their diffusion profiles modeled.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOTK059

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS005

SOLEIL Machine Status and Upgrade

injection, lattice, photon, synchrotron

1397

L.S. Nadolski, G. Abeillé, Y.-M. Abiven, F. Bouvet, P. Brunelle, N. Béchu, M.-E. Couprie, X. Delétoille, S. Duigou, A. Gamelin, C. Herbeaux, N. Hubert, M. Labat, J.-F. Lamarre, V. Le Roux, A. Lestrade, A. Loulergue, O. Marcouillé, F. Marteau, A. Nadji, R. Nagaoka, M. Nouna, Y. Rahier, F. Ribeiro, G. Schaguene, K. Tavakoli, M.-A. Tordeux
SOLEIL, Gif-sur-Yvette, France
S. Ducourtieux
LNE, Trappes Cedex, France

SOLEIL is both a 2.75 GeV third generation synchrotron light source and a research laboratory at the forefront of experimental techniques dedicated to matter analysis down to the atomic scale, as well as a service platform open to all scientific and industrial communities. We present the performance of the accelerators delivering extremely stable photon beams to 29 beamlines. We report on the commissioning of a superbend magnet replacing a standard 1.71T dipole with a 2.84 T narrow peak permanent magnet-based dipole. It required local modification of the lattice to compensate linear and nonlinear optics distortions introduced by the new magnet field. The latest measurements made with a Multipole Injection Kicker are also reported. Work on the NEG test bench and its dedicated front-end for a 10 mm inner diameter vacuum pipe and other major R&D areas are also addressed in the frame of the SOLEIL upgrade.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS005

About •

Received ※ 10 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS011

Progress Towards EEHG Seeding at the DELTA Storage Ring

laser, electron, undulator, storage-ring

1420

B. Büsing, A. Held, H. Kaiser, S. Khan, C. Mai, A. Radha Krishnan
DELTA, Dortmund, Germany

Funding: Funded by BMBF (05K16PEB, 05K19PEB), FZ Jülich, and by the federal state NRW.
Seeding of free-electron lasers (FELs) with external laser pulses triggers the microbunching process such that the spectrotemporal properties of coherently emitted FEL radiation are under better control compared to self-amplified spontaneous emission. High-gain harmonic generation (HGHG) based on the interaction of electrons with a single laser pulse is routinely applied at a few FELs, and echo-enabled harmonic generation (EEHG) with a twofold laser-electron interaction has been demonstrated. Both schemes can be adopted in storage rings for the coherent emission of ultrashort radiation pulses. Coherent harmonic generation (CHG) is the counterpart to HGHG without FEL gain. It has been employed at several storage rings and presently provides ultrashort pulses in the vacuum ultraviolet regime at the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University. EEHG, which allows to reach higher harmonics of the seed wavelength, has not yet been implemented at any storage ring but is pursued at DELTA as an upgrade plan. The paper presents the layout of the envisaged EEHG facility, and it reviews simulation studies and the technical progress towards EEHG seeding at DELTA.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS011

About •

Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 29 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS015

Proposal of a Girder Realignment Test in PETRA III

alignment, controls, storage-ring, experiment

1435

M. Schaumann, I.V. Agapov, R. Bartolini, M. Bieler, R. Böspflug, D. Einfeld, M.G. Hoffmann, J. Keil, L. Liao, G. Priebe, M. Schlösser, R. Wanzenberg
DESY, Hamburg, Germany

PETRA IV can benefit from the fine control of the girders that carry the storage ring elements to achieve the design beam performance. Based on the corrector magnet strength pattern it is desired to realign girders to stay within the alignment tolerances. In the current PETRA III configuration, the girders in the Max von Laue Hall are equipped for remote alignment, however, those have not been moved since their initial installation and the alignment system is currently not connected to the control system. In preparation for PETRA IV, a movement test of one of the PETRA III girders should confirm the ability to safely and precisely remote control the equipment based on an optics model that describes the effect of the girder movement on the orbit. This paper studies the feasibility of this test and prepares an initial mock-up experiment to be performed on a spare girder.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS015

About •

Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS022

Cooling Challenges in a NEG-Coated Vacuum Chamber of a Light Source

simulation, radiation, software, synchrotron

1456

S. Talebi Motlagh, A. Danaeifard, J. Rahighi, F. Saeidi
ILSF, Tehran, Iran
F. Zamani
University of Kashan, Kashan, Iran

In a light Source, unused synchrotron radiation is being distributed along the walls of the chambers. Due to the small conductance of the chambers, vacuum pumping is based on the distributed concept, and then non-evaporable getter (NEG) coating is extensively used. The vacuum chambers are made of copper alloys tube, and cooling circuits are welded to the chamber to remove the heat load from the radiation generated. Filler metal is used to create a brazed joint between the water cooling pipe and the vacuum chamber body. The thermal conductivity of the fillers is less than the vacuum chamber body. Moreover, the water velocity in the cooling pipe must be taken into account in thermal calculations. In this paper, we study and investigate the effects of the filler metal and the cooling water velocity in cooling the chambers.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS022

About •

Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS052

Considerations From Deploying, Commissioning, and Maintaining the Control System for LCLS-II Undulators

undulator, controls, MMI, EPICS

1546

M.A. Montironi, C.J. Andrews, G. Marcus, H.-D. Nuhn
SLAC, Menlo Park, California, USA

Funding: This work was supported by Department of Energy, Office of Basic Energy Sciences, contract DE-AC02-76SF00515
Two new undulator lines have been installed as part of the Linac Coherent Light Source upgrade (LCLSII) at SLAC National Accelerator Laboratory. One undulator line, composed of 21 horizontally polarizing undulator segments, is dedicated to producing Soft X-Rays (SXR). The other line, composed of 32 vertically polarizing undulator segments, is dedicated to producing Hard X-Rays (HXR). The devices were installed, and the control system was deployed in 2019. Commissioning culminated with the achievement of first light from the HXR undulator in the Summer of 2020 and from the SXR undulator in the Fall of 2020. Since then, both undulator lines have been successfully providing x-Rays to user experiments with very limited downtime. In this paper, we first describe the strategies utilized to simplify the deployment, commissioning, and maintenance of the control system. Such strategies include scripts for automated components calibration and monitoring, a modular software structure, and debugging manuals for accelerator operators. Then, we discuss lessons learned which could be applicable to similar projects in the future.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS052

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 26 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIYSP1

New Designs of Short-Period Undulators for Producing High-Brightness Radiation in Synchrotron Light Sources

undulator, radiation, cryogenics, synchrotron

1624

E.J. Wallén
LBNL, Berkeley, California, USA

We review modern state-of-the-art and new concepts of undulators planned for new generation light sources. Both superconducting and permanent-magnet-based insertion devices feature unique solutions to reach high precisely tunable fields in the period range of 10^-18 mm, 2-4 meters in length and with the ID gaps of less than 5 mm. The same quest for small gaps and shortest possible period length exists also for elliptically polarizing undulators. A review of new designs in Europe, Asia and Americas will be in the focus of this presentation.

Slides WEIYSP1 [21.171 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIYSP1

About •

Received ※ 15 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 07 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIZSP2

Trapping of Neutral Molecules by the Electromagnetic Beam Field

dipole, electron, simulation, alignment

1649

G. Franchetti
GSI, Darmstadt, Germany
F. Zimmermann
CERN, Meyrin, Switzerland

Neutral uncharged molecules are affected by the electromagnetic field of a charged particle beam if they carry either an electric or a magnetic dipole moment. The residual gas in an accelerator beam pipe consists of such molecules. In this paper we study their dynamics. Under a few approximations, whose validity we explore and justify, we derive the equations of motion of neutral molecules and their invariants, determine the conditions for these neutral molecules to become trapped in the field of the beams as function of beam-pipe temperature, and compute the resulting enhancement of molecule density in the vicinity of the beam. We demonstrate that large agglomerates of molecules, "flakes," are much more likely to be pulled into the beam than single molecules, and suggest that this phenomenon might help explain some beam observations at the Large Hadron Collider.

Slides WEIZSP2 [6.142 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEIZSP2

About •

Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT045

Transverse Electron Beam Tails and Beam Lifetime in the EIC Electron Storage Ring

electron, simulation, proton, storage-ring

1958

C. Montag
BNL, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704.
While for most storage ring design activities it is sufficient to assume a Gaussian distribution of the beam particles, a more detailed prediction of the population in the transverse tails is necessary to predict the beam lifetime in a given aperture. Dominant processes that result in non-Gaussian distributions are the beam-beam interaction in a collider as well as beam-gas scattering. Simulations to determine the required apertures and vacuum levels in the EIC electron storage ring will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT045

About •

Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK023

Simulation Study of Fast Extraction in the Absence of One Septum Magnet for J-Parc Main Ring

septum, operation, extraction, kicker

2100

S. Iwata, S. Igarashi, K. Ishii, H. Matsumoto, N. Matsumoto, Y. Sato, T. Shibata, T. Sugimoto, T.Y. Yasui
KEK, Tokai, Ibaraki, Japan

At J-PARC main ring (MR), the two fast extracting beamlines to the neutrino facility and to the abort dump have a symmetrical layout of 6 septum magnets each, a total of 12. Since there are many magnets, it is necessary to be careful about failure. It is important to consider how to continue beam supply even if one of the septum mag-nets is missing. From July 2021, upgrade works of the FX septum magnets commenced with an aim of increasing the beam power of MR to 1.3 MW from 500 kW. We simulated the beam extraction without one of the septum magnets under the conditions of the new geometry of septum magnets and the new aperture. We found that the beam can be extracted by increasing the current of the surrounding septum magnets and compensating for the output.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK023

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK024

Upgrade of Septum Magnets for Fast Extraction in J-Parc Main Ring

septum, operation, extraction, power-supply

2103

S. Iwata, K. Ishii, H. Matsumoto, N. Matsumoto, Y. Sato, T. Shibata, T. Sugimoto, M. Uota
KEK, Tokai, Ibaraki, Japan

We aim to supply a high-power proton beam of 1.3 MW to the neutrino facility from J-PARC Main Ring (MR) by shortening the repetition cycle to 1.16 s from 2.48 s and increasing the number of particles by 30%. The six sep-tum magnets for fast extraction (FX) need to be replaced to reduce the heat that is generated as a result of shorten-ing the repetition cycle. The replacement of the septum magnets began in July 2021 and was completed at the end of May 2022. The beam commissioning starts in June 2022. We report the details of the replacement work and operation test of the new septum magnets. We found a defect in the magnetic coil of the septum (SM32) in August 2021. We decided to postpone its installation to around August 2022 and produce new magnet coils for the SM32. The beam extraction in June 2022 will be per-formed using a temporary vacuum duct instead of the SM32 magnet, and the extraction beam orbit will be maintained by increasing the magnetic field of the other five septum magnets.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK024

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK052

Beam Coupling Impedance Study and Its Database of Siam Photon Source Storage Ring

impedance, storage-ring, wakefield, simulation

2177

N. Juntong, T. Chanwattana, S. Jummunt, K. Kittimanapun, T. Phimsen, W. Promdee, T. Pulampong
SLRI, Nakhon Ratchasima, Thailand

Since the Siam Photon Source (SPS) had an electron beam energy upgraded from 1.0 GeV to 1.2 GeV in 2005, the storage ring impedance measurements were done once in 2007. Two insertion magnet devices have been installed in the SPS storage ring during June to August 2013. There are several vacuum components added to the storage ring; these affect the ring impedance. Quantitative understanding of instabilities requires detailed knowledge of the impedance of the ring. For this purpose, the development of an impedance database is a necessity, where the wake potentials of each vacuum component are kept and maintained in a standard format. The self-describing data sets (SDDS) file format will be utilized to record components wake potentials. The wake potentials of each vacuum component can be obtained from a particle tracking simulation; a CST particle studio program will be used in the simulation process. The wake potentials can also be included in a beam dynamic tracking program such as ELEGANT to observe beam behaviors with these instabilities and find a curing means. The study results will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK052

About •

Received ※ 19 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK055

Beam Lifetime Measurements in Sirius Storage Ring

storage-ring, scattering, simulation, synchrotron

2186

M.B. Alves, L. Liu, X.R. Resende, F.H. de Sá
LNLS, Campinas, Brazil

SIRIUS is the new storage ring-based 4th generation synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS) at the Brazilian Center for Research in Energy and Materials (CNPEM). In ultralow emittance storage rings such as SIRIUS, the dominant contribution to the beam lifetime is due to large angle scattering between electrons within the same bunch, namely the Touschek effect. We used the strategy of storing two bunches simultaneously with different currents to measure their Touschek lifetime independently of other contributions, such as gas scattering. The measurements were carried out in different conditions of bunch current and RF voltage to compare the experimental results with those expected from theory and simulations for SIRIUS.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK055

About •

Received ※ 08 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 24 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THIXSP1

A New Compact 3 GeV Light Source in Japan

cavity, electron, emittance, quadrupole

2402

N. Nishimori
QST, Tokai, Japan

A new 3 GeV light source with a circumference of 350 m and an MBA lattice has been officially funded and is being constructed in north-eastern Japan. Aiming at stable and high-performance operations with an emittance of about 1 nm rad, various design and R&D activities are being performed: the four bend achromatic lattice using BQ combined function magnets; the compact RF system using a TM020 mode and in-cavity compact HOM absorbers; the in-vacuum off-axis injection scheme enabling stored beam oscillation-free injections with a small injection beam amplitude; the injector linac composed of a thermionic E-gun and C-band accelerators with a capability of extension to feed a future SX-FEL driver, and so on. The installation of accelerator components is ongoing. The talk will include the overall design of the light source, R&D results, and the latest construction status.

Slides THIXSP1 [15.084 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THIXSP1

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 25 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST025

Operational Experience with the Improved VSR DEMO Collimating Shielded Bellow in BESSY II

operation, SRF, cavity, synchrotron

2497

H.-W. Glock, V. Dürr, F. Glöckner, J. Knobloch, M. Ries, A. Vélez
HZB, Berlin, Germany
J. Knobloch
University of Siegen, Siegen, Germany
A. Vélez
Technical University Dortmund, Dortmund, Germany

Funding: Work supported by grants of the Helmholtz Association
The Collimating Shielded Bellow (CsB) is designed to serve both as a flexible beam pipe connection between two adjacent superconducting cavities as foreseen in VSR DEMO and as a synchrotron light collimator to shield the down-stream cavity from synchrotron radiation. A convoluted inner RF shield was applied to prevent fundamental mode heating of the stainless-steel-made bellow in the cryogenic environment, making the such captured inner volume very difficult to access for inspection and cleaning. A first version of the device was successfully tested as part of the beam pipe of the synchrotron light source BESSY II under regular operation for more than a year. It suffered from an unfavorable long outgassing commissioning. Therefore a detachable design, allowing for rigorous inner surface preparation and cleaning, was built and recently installed in BESSY II. CsB version 2 design and experimental outcomes are described in the paper. First results indicated a significantly improved vacuum commissioning performance, which was confirmed later on.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST025

About •

Received ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 10 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST027

Fabrication of Robust Thermal Transition Modules and First Cryogenic Experiment with the Refurbished COLDDIAG

operation, cryogenics, diagnostics, experiment

2505

H.J. Cha, N. Glamann, A.W. Grau, A.-S. Müller, D. Saez de Jauregui
KIT, Eggenstein-Leopoldshafen, Germany

Funding: This work is supported by the BMBF project 05H18VKRB1 HIRING (Federal Ministry of Education and Research).
Two sets of thermal transition modules as a key component for the COLDDIAG (cold vacuum chamber for beam heat load diagnostics) refurbishment were manufactured, based on the previous design study. The modules are installed in the existing COLDDIAG cryostat and tested with an operating temperature of approximately 50 K at both a cold bore and a thermal shield. This cool-down experiment is a preliminary investigation aiming at beam heat-load studies at the FCC-hh where the beam screens will be operated at almost the same temperature. In this contribution, we report the fabrication processes of the mechanically robust transition modules and the first thermal measurement results with the refurbished COLDDIAG in a cryogenic environment. The static heat load in the refurbished cryostat remains unchanged, compared to that in the former one (4-K cold bore and 50-K shield with thin transitions), despite the increase in the transition thickness. It originates from the identical temperature at the cold bore and the shield, which can theoretically allow the heat intakes by thermal conduction and radiation between them to vanish.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST027

About •

Received ※ 16 May 2022 — Accepted ※ 13 June 2022 — Issue date ※ 10 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST035

Status of the Engineering Design of the IFMIF-DONES High Energy Beam Transport Line and Beam Dump System

target, beam-transport, diagnostics, neutron

2520

D. Sánchez-Herranz, O. Nomen, M. Sanmartí, B.K. Singh
IREC, Sant Adria del Besos, Spain
F. Arranz, C. Oliver, I. Podadera
CIEMAT, Madrid, Spain
P. Cara
IFMIF/EVEDA, Rokkasho, Japan
V. Hauer
KIT, Eggenstein-Leopoldshafen, Germany
F. Ogando
UNED, Madrid, Spain
D. Sánchez-Herranz
UGR, Granada, Spain

Funding: Work performed within framework of EUROfusion Consortium, funded by European Union via Euratom Research & Training Programme (Grant Agreement 101052200’EUROfusion). Views & opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Commission. Neither European Union nor European Commission can be held responsible for them.
IFMIF-DONES plant (International Fusion Materials Irradiation Facility ’ DEMO Oriented Neutron Source) will be an installation located in the south of Spain at Granada. Its objective is the fusion material testing by the generation of a neutron flux with a broad energy distribution covering the typical neutron spectrum of a (D-T) fusion reactor. This is achieved by the Li(d, xn) nuclear reactions occurring in a liquid lithium target where a 40 MeV at 125 mA deuteron beam with a variable rectangular beam footprint between 100mm x 50mm and 200mm x 50mm collides. The accelerator system is in charge of providing such high energy deuterons in order to produce the required neutron flux. The High Energy Beam Transport line is the last subsystem of the IFMIF-DONES accelerator and its main functions are to guide the deuteron beam towards the liquid lithium target and to shape it with the required rectangular reference beam footprint. The present work details the status of the HEBT engineering design, including beam dynamics, vacuum configuration, radioprotection, beam diagnostics devices and remote handling analyses performed detailing the layout and integration.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST035

About •

Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 14 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOST039

SPS Beam Dump System (SBDS) Commissioning After Relocation and Upgrade

kicker, MMI, controls, hardware

2530

P. Van Trappen, E. Carlier, L. Ducimetière, V. Namora, V. Senaj, F.M. Velotti, N. Voumard
CERN, Meyrin, Switzerland

In order to overcome several machine limitations, the SBDS has been relocated from LSS1 (Long Straight Section 1) to LSS5 during LS2 (Long Shutdown 2) with an important upgrade of the extraction kicker installation. An additional vertical deflection kicker magnet (MKDV) was produced and installed while the high voltage (HV) pulse generators have been upgraded by changing gas-discharge switches (thyratrons and ignitrons) to semiconductor stacks operating in oil. Furthermore the horizontal sweep generators have been upgraded to allow for a lower kick strengths. The controls, previously consolidated during LS1, went through an additional light consolidation phase with among others the upgrade of the trigger & retrigger distribution system and the installation of a new fast-interlocks detection system. This paper describes the commissioning without and with beam and elaborates on the measured improvements and encountered problems with corrective mitigations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOST039

About •

Received ※ 07 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 15 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT004

Design of a Compact 180-Degree Single-Shot Energy Spectrometer Based on a Halbach Dipole Magnet

electron, dipole, simulation, detector

2564

R. Bazrafshan, T. Rohwer
Deutsches Elektronen Synchrotron (DESY) and Center for Free Electron Science (CFEL), Hamburg, Germany
M. Fakhari, N.H. Matlis
CFEL, Hamburg, Germany
F.X. Kaernter
DESY, Hamburg, Germany

In the AXSIS project at DESY, we develop compact THz accelerating structures for a table-top x-ray source. Acceleration is achieved by passing the electron beam through a dielectric-loaded waveguide powered by multi-cycle THz radiation. The final electron energy strongly depends on THz-power injected into the LINAC and timing. Thus in first experiments we expect large energy fluctuations and a large range of energies to cover. We designed an electron energy spectrometer for a wide range of final energies covering 5 to 20 MeV in a single-shot. Here, we present the design of an energy spectrometer which uses a compact dipole magnet based on the Halbach array concept to deflect the electron beam through a 180° path intercepted by a Fiber Optic Scintillator (FOS) mounted inside the vacuum perpendicular to the beam. The 180-degree bending geometry provides the possibility of having the focus point of all energies at the same distance from the magnet edge which makes the design simpler and more compact. It also removes the necessity of installing a safety dipole at the end of the accelerator. A slit system at the spectrometer entrance increases resolution to better than 0.2%.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT004

About •

Received ※ 08 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT008

Beam Orbit Shift Due to BPM Thermal Deformation Using Machine Learning

network, storage-ring, synchrotron, feedback

2577

K.M. Chen, M. Hosaka, F.Y. Wang, G. Wang, Z. Wang, W. Xu
USTC/NSRL, Hefei, Anhui, People’s Republic of China
L. Guo
Nagoya University, Nagoya, Japan

Stabilizing beam orbit is critical for advanced synchrotron radiation light sources. The beam orbit can be affected by many sources. To maintain a good orbit stability, global orbit feedback systems (OFB) has been widely used. However, the BPM thermal deformation would lead to BPM misreading, which can not be handled by OFB. Usually, extra diagnostics, such as position transducers, is needed to measure the deformation dependency of BPM readings. Here, an alternative approach by using the machine operation historic data, including BPM temperature, insertion device (ID) gaps and corrector currents, is presented. It is demonstrated at Hefei Light Source (HLS). The average orbit shift due to BPM thermal deformation is about 34.5 microns/degree Celsius (horizontal) and 20.0 microns/degree Celsius (vertical).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT008

About •

Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 19 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT022

Study on QE Evolution of Cs₂Te Photocathodes in ELBE SRF Gun-II

cathode, gun, SRF, operation

2617

R. Xiang, A. Arnold, S. Ma, P. Michel, P. Murcek, A.A. Ryzhov, J. Schaber, J. Teichert, P.Z. Zwartek
HZDR, Dresden, Germany

The quality of the photocathodes is critical for the sta-bility and reliability of the photoinjector’s operation. Thanks to the robust magnesium and Cs₂Te photocathodes, SRF gun-II at HZDR has been proven to be a suc-cessful example in CW mode for high current user operation. In this contribution, we will present our observation of the QE evolution of Cs₂Te photocathodes during SRF gun operation. The variables including substrate surface, film thickness, Cs/Te stoichiometric, multipacting, RF loading and charge extract are considered in the analysis.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT022

About •

Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 06 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT032

SUNDAE2 at EuXFEL: A Test Stand to Characterize the Magnetic Field of Superconducting Undulators

undulator, FEL, laser, experiment

2649

J.E. Baader, S. Abeghyan, S. Casalbuoni, D. La Civita, B. Marchetti, M. Yakopov, P. Ziolkowski
EuXFEL, Schenefeld, Germany
H.-J. Eckoldt, A. Hauberg, S. Lederer, L. Lilje, T. Wohlenberg, R. Zimmermann
DESY, Hamburg, Germany
A.W. Grau
KIT, Eggenstein-Leopoldshafen, Germany

European XFEL foresees a superconducting undulator (SCU) afterburner in the SASE2 hard X-ray beamline. It consists of six 5m-long undulator modules with a 5mm vacuum gap, where each module contains two 2m-long coils and one phase shifter. Prior to installation, the magnetic field must be mapped appropriately. Two magnetic measurement test stands named SUNDAE 1 and 2 (Superconducting UNDulAtor Experiment) are being developed at European XFEL. While SUNDAE1 will be a vertical test stand to measure SCU coils up to two meters with Hall probes in a liquid or superfluid helium bath, SUNDAE2 will measure the SCU coils assembled in the final cryostat. This contribution presents the development status of SUNDAE2 and its main requirements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT032

About •

Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT033

Performance Characterisation at Daresbury Laboratory of Cs-Te Photocathodes Grown at CERN

cathode, electron, emittance, cryogenics

2653

L.A.J. Soomary, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
C. Benjamin, H.M. Churn, L.B. Jones, T.C.Q. Noakes
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
C. Benjamin
University of Warwick, Coventry, United Kingdom
E. Chevallay, V.N. Fedosseev, E. Granados, M. Himmerlich, H. Panuganti
CERN, Meyrin, Switzerland
L.B. Jones, T.C.Q. Noakes, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: STFC Doctoral Training Studentship
The search for high-performance photocathodes is a priority in the field of particle accelerators. The surface characteristics of a photocathode affect many important factors of the photoemission process including the photoemission threshold, the intrinsic emittance and the quantum efficiency. These factors in turn define the electron beam quality, which is measurable using figures of merit like beam emittance, brightness and energy spread. We present characterisation measurements for four caesium telluride photocathodes synthesized at CERN. The photocathodes were transported under ultra-high vacuum (UHV) and analysed at STFC Daresbury Laboratory, using ASTeC’s Multiprobe (SAPI)* for surface characterisation via XPS and STM, and for Mean Transverse Energy (MTE) measurements using the Transverse Energy Spread Spectrometer (TESS)**. The MTE measurements were estimated at cryogenic and room temperatures based on the respective transverse energy distribution curves. We discuss correlations found between the synthesis parameters, and the measured surface characteristics and MTE values.
*B.L. Militsyn, 4-th EuCARD2 WP12.5 meeting, Warsaw, 14-15 March 2017
**L.B. Jones et al., Proc. FEL ’13, TUPPS033, 290-293; https://accelconf.web.cern.ch/FEL2013/papers/tupso33.pdf

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT033

About •

Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 05 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT037

Ceramics Evaluation for MW-Power Coaxial Windows, Operating in UHF Frequency Range

Windows, electron, multipactoring, cavity

2668

S.V. Kutsaev, R.B. Agustsson, P.R. Carriere, N.G. Matavalam, A.Yu. Smirnov, S.U. Thielk
RadiaBeam, Santa Monica, California, USA
A.A. Haase
SLAC, Menlo Park, California, USA
T.W. Hall, D. Kim, J.T.M. Lyles, K.E. Nichols
LANL, Los Alamos, New Mexico, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Basic Energy Science, under SBIR grant DE- SC0021552
Modern accelerator facilities require reliable high-power RF components. The RF vacuum window is a critical part of the waveguide couplers to the accelerating cavities. It is the point where the RF feed crosses the vacuum boundary and thus forms part of the confinement barrier. RF windows must be designed to have low power dissipation inside their ceramic, be resistant to mechanical stresses, and free of discharges. In this paper, we report on the evaluation of three different ceramic candidates for high power RF windows. These materials have low loss tangents, low secondary electron yield (SEY), and large thermal expansion coefficients. The acquired materials were inspected, coated, and measured to select the optimal set.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT037

About •

Received ※ 01 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 04 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT047

A Double Dipole Kicker for Off and On-Axis Injection for ALBA-II

kicker, injection, dipole, storage-ring

2701

G. Benedetti, M. Carlà, M. Pont
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain

Injection into the ALBA-II storage ring will be performed off-axis in a 4 meters straight section with a single multipole kicker. We present a novel topology for the coils of the injection kicker, named double dipole kicker (DDK). The resulting magnetic field is the superposition of two opposite dipoles, generated by four inner and four outer conductor rods. When the eight rods are powered, the dipole term cancels and the remaining multipole field is used for off-axis injection. Alternatively, when the four inner rods are switched off, an almost pure dipole is produced, that is useful for on-axis injection during the commissioning. A prototype of DDK is presently under design to be installed and tested in the existing ALBA storage ring. The positioning of the rods is calculated in order to maximise the kick efficiency in mrad/kA and minimise the disturbance to the orbit and the emittance of the stored beam. A metallic coating with optimised thickness along the inner ceramic vacuum chamber should provide compensation for the eddy currents induced field in order to minimize the disturbance to the stored beam while ensuring sufficiently low heat dissipation by the beam image currents.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT047

About •

Received ※ 16 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 20 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT050

Development and Construction of Cryogenic Permanent Magnet Undulators for ESRF-EBS

undulator, SRF, permanent-magnet, cryogenics

2712

C. Benabderrahmane, P. Brumund, J. Chavanne, D. Coulon, G. Le Bec, B. Ogier, R. Versteegen
ESRF, Grenoble, France

The ESRF Extremely Brilliant Source (ESRF-EBS) is on operation for Users since August 2020 after 20 months of shutdown. This first of a kind fourth generation high energy synchrotron is based on a Hybrid Multi-Bend Achromat lattice. The main goal of the ESRF-EBS is to reduce the horizontal emittance, which leads to a signifi-cant increase of the X-ray source brilliance. To cover the intensive demand of short period small gap undulators at ESRF-EBS, a new design for a 2 m Cryogenic Permanent Magnet Undulator (CPMU) has been developed. Six CPMUs will be installed in the next years; the first two CPMUs have been constructed and actually used on ID15 and ID16 beamline, the third one is under con-structing. An intensive refurbishment work has been done on the existing insertion devices to adapt them to the new accelerator which has shorter straight section and closer dipoles to the IDs than in the old one. This contribution will review the development, construc-tion and commissioning of the new CPMUs, and the refurbishment work done on the existing ones to adapt them to the new accelerator.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT050

About •

Received ※ 02 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 18 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT052

The Status of the In-Vacuum-APPLE II Undulator IVUE32 at HZB / BESSY II

undulator, shielding, photon, polarization

2716

J. Bahrdt, J. Bakos, S. Gaebel, S. Gottschlich, S. Grimmer, S. Knaack, C. Kuhn, F. Laube, A. Meseck, C. Rethfeldt, E.C.M. Rial, A. Rogosch-Opolka, M. Scheer, P.I. Volz
HZB, Berlin, Germany

At BESSY II, two new beamlines for RIXS and for X-Ray-microscopy demand a short period variably polarizing undulator. For this purpose, the first in-vacuum APPLE undulator worldwide is under construction. The parameters are as follows: period length=32mm, magnetic length=2500mm, minimum gap=7mm. The design incorporates a force compensation scheme as proposed by two of the authors at the SRI2018. All precision parts of the drive chain are located in air. New transverse slides for the transversal slit adjustment have been developed and tested. Optical micrometers measure the gap and shift positions, similar to the system of the CPMU17 at BESSY II. They provide the signals for motor feedback loops. A new UHV-compatible soldering technique, as developed with industry, relaxes fabrication tolerances of magnets and magnet holders and simplifies the magnet assembly. A 10-period prototype has been setup for lifetime tests of the new magnetic keeper design. The paper describes first results of the prototype and other key-components and summarizes the status of the full-scale undulator.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT052

About •

Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 11 June 2022 — Issue date ※ 22 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT053

Goubau-Line Set Up for Bench Testing Impedance of IVU32 Components

impedance, simulation, undulator, cavity

2719

P.I. Volz, A. Meseck
HZB, Berlin, Germany
A. Meseck
KPH, Mainz, Germany

The worldwide first in-vacuum elliptical undulator, IVUE32, is being developed at Helmholtz-Zentrum Berlin. The 2.5 m long device with a period length of 3.2 cm and a minimum gap of about 7 mm is to be installed in the BESSY II storage ring. It will deliver radiation in the soft X-ray range to several beamlines. The proximity of the undulator structure to the electron beam makes the device susceptible to wakefield effects which can influence beam stability. A complete understanding of its impedance characteristics is required prior to installation and operation, as unforeseen heating of components could have catastrophic consequences. To understand and measure the IVU’s impedance characteristics a Goubau-Line test stand is being designed. A Goubau-line is a single wire transmission line for high frequency surface waves with a transverse electric field resembling that of a charged particle beam out to a certain radial distance. A concept optimized for bench testing IVUE32-components will be discussed, microwave simulations will be presented together with first measurements from a test stand prototype.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT053

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 16 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK027

Temperature Dependent Effects on Quality Factor in C-band RF Cavities

cavity, cryogenics, shielding, electron

2826

J.R. Parsons, A. Fukasawa, G.E. Lawler, N. Majernik, J.B. Rosenzweig
UCLA, Los Angeles, California, USA

Funding: This work was supported by DOE Contract DE-SC0020409
Cryogenic operation and associated skin effects are encouraging fields of study for increasing RF gradients of beams within cavities and decreasing the required size for linear accelerators such as free electron lasers. Notably, a cavity’s RF quality factor Q, the ratio of the outgoing RF signal power to the input power, is theoretically multiplied by over 4 when subjected to cryogenic temperatures. Precise measurements of this Q factor require defining a cryostat unit, which consists of a high vacuum chamber, a coldhead, and MLI shielding. We optimized the cryostat by running several cool down tests at high vacuum, incorporating different geometries of MLI shielding to achieve the lowest possible temperatures. We then performed a low power C-band test after installing a cylindrical copper RF cavity to measure the Q factor. Finally, we improved stability and amplification within the chamber by installing edge welded bellows to the coldhead to reduce vibrations. These measurements provide a basis for the development of cryogenic infrastructure to sustain a cryogenic temperature environment for future RF applications.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK027

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 27 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK032

A Vacuum System for the Milliampere Booster

cavity, simulation, linac, experiment

2833

R.G. Heine, C.L. Lorey
KPH, Mainz, Germany

The Milliampere Booster (MAMBO) is the injector linac for the Mainz Energy-recovering Superconducting Accelerator MESA. MESA is a multi-turn energy recovery linac with beam energies in the 100 MeV regime currently designed and built at Institut für Kernphysik (KPH) of Johannes Gutenberg-Universität Mainz. The main accelerator consists of two superconducting Rossendorf type modules, while the injector MAMBO relies on normal conducting technolgy. The MAMBO RF cavities are bi-periodic pi/2 structures that are about 2m long, each. In this paper we present the results of Molflow+ simulations of several setups of the vacuum system for MAMBO that differ in number of pumps, pumping speed and diameter of the pumping ports that are connected to the DN40 beam pipe.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK032

About •

Received ※ 07 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 24 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK034

Vacuum System Performance of the 3 GeV Electron Storage Ring at MAX IV Laboratory

storage-ring, operation, MMI, injection

2836

M.J. Grabski, E. Al-Dmour, S.M. Scolari
MAX IV Laboratory, Lund University, Lund, Sweden

The 3 GeV electron storage ring at MAX IV laboratory is the first synchrotron light source with compact multi-bend achromat (MBA) magnet lattice to achieve ultra-low emittance. The vacuum system of the accelerator is fully coated with non-evaporable getter (NEG) thin film to ensure low gas density. The storage ring started commissioning in August 2015 and currently delivers photon beams from insertion devices (IDs) to 9 beamlines that are in user operation or commissioning. After over 6 years of operation, the NEG coated vacuum system continues to be reliable, is conditioning well and do not pose any limitation to the accelerator operation. The average dynamic pressure is lower than the design value (below 3·10^-10 mbar) and is reducing with the accumulated beam dose. The vacuum beam lifetime is greater than 39 Ah, and the total beam lifetime is above the design value of 5 Ah - thus is not limited by the residual gas density. Several successful interventions to install new vacuum components were performed on few achromats in the storage ring during shutdowns. Some of them were done utilizing purified neon gas to vent the vacuum system, thus avoiding the need of re-activation of the NEG coating and saving intervention time without compromising the storage ring performance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK034

About •

Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 28 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK035

Thermo-Mechanical Modeling and Thermal Performance Analysis of Beam Vacuum Line Interconnections and Cold Warm Transitions in HL-LHC Long Straight Section Magnets

cryogenics, luminosity, radiation, insertion

2839

J. Harray, C. Garion, V. Petit
CERN, Meyrin, Switzerland

The HL-LHC upgrade, aiming at increasing the LHC levelled luminosity by factor of five, relies on new superconducting magnets requiring a new beam vacuum system. Along with the challenges related to magnet design, the beam optic configuration exposes this new equipment to stringent conditions for vacuum and cryogenic performance. Both cold-warm transitions and magnet interconnections appear to be delicate components that are crucial for the thermal heat transfer between diverse subsystems. The proposed study aims at assessing the heat loads to the cryogenic system and the temperature fields in the vacuum system. A nonlinear static thermal analysis is first performed. A thermo-mechanical approach is developed to capture additional thermal resistance arising from contact between components and their behaviour during cool-down. The system is then studied under dynamic operations when beams are circulating and colliding. A thorough analysis of beam-induced heat loads under ultimate conditions highlights the different relevant contributions. Finally, the transient response of the systems is computed to assess thermal time constants.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK035

About •

Received ※ 08 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 27 June 2022 — Issue date ※ 29 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK036

Determination of Pumping and Dynamic Vacuum Properties of Conductive Quaternary Alloy of TiZrVAg Non-Evaporable Getter.

photon, electron, experiment, site

2843

R. Valizadeh, A.N. Hannah, O.B. Malyshev
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
G.Y. Hsiung
NSRRC, Hsinchu, Taiwan
J.M. O’Callaghan Castella
Universitat Politécnica de Catalunya, Barcelona, Spain
M. Pont, N.D. Tagdulang
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain

Non Evaporable Getter (NEG) coating has been employed extensively in the particle accelerator especially where the vacuum conductance of the vessel is severely restricted and ultra-high vacuum condition is required. NEG coating will significantly reduce the outgassing rate and provides active pumping surface for H₂, CO and CO₂. In addition, it has been proven that NEG coated surfaces have a very low secondary electron yield, as well as low photon and electron stimulated desorption yields. However, the existing NEG film increases the RF surface resistance of the beam pipe. In order to increase NEG coating conductivity, at ASTeC, in the past several years, the alternative NEG com-position have been studied by adding more conductive element such as Cu, Au, Al and Ag. In this study, we report on the photon stimulated desorption, activation temperature and surface resistance from room temperature to cryogenic temperature for a new NEG quaternary alloy of TiVZrAg as function of the film composition.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK036

About •

Received ※ 07 June 2022 — Revised ※ 11 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK037

Measurement of the Photon Stimulated Desorption for Various Vacuum Tubes at a Beam Line of TLS

photon, experiment, radiation, synchrotron

2847

G.Y. Hsiung, C.M. Cheng
NSRRC, Hsinchu, Taiwan
R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

For most light sources, the synchrotron radiation (SR) hit on the beam ducts or absorbers results in higher pressure rise and the consequent higher radiation level through the commissioning stage. Various surface treatments, e.g. chemical cleaning, oil-free machining, NEG-coating, etc., for the beam ducts or absorbers have been developed worldwide for mitigating the yield of Photon Stimulated Desorption (PSD). A beam line, BL19B, of 1.5 GeV Taiwan Light Source (TLS) has been modified to measure the PSD-yield of the vacuum tubes. The white light of BL19B covers the critical length at 2.14 keV is suitable for generating higher yield of the photo-electrons (PEY) and the consequent PSD-yield to be measured can be resolved wide range of 10^-2 ~ 10^-7 molecules/photon. The PSD-outgas, measured by RGA, contains the typical H₂, CO, CO₂, hydrocarbons, and Kr from NEG-coating, alcohol from ethanol machined surface, in some cases. The effect of beam-cleaning reflects the PSD-molecules generated from the SR-irradiated surface. The comparison of the PSD for the various vacuum tubes will be described in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK037

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 08 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK038

Electron Stimulated Desorption From Titanium Tube

electron, radiation, photon, experiment

2850

O.B. Malyshev, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Titanium is one of material that used for production of accelerator vacuum chamber and components. In this paper we report the results of vacuum properties evaluation measurements of titanium vacuum chamber. The sample was produced from 40-mm inner diameter tube made of titanium and equipped with CF40 flanges at both ends. The electron stimulated desorption (ESD) was measured after 24-h bakeout to 80, 150, 180 and 250 oC. H₂ and CO initial sticking probabilities were measured after bakeout before the ESD measurements. After ESD measurements, the initial H₂ and CO sticking probabilities were measured again together with CO sorption capacity. These measurements provide the results for ESD as a function of electron dose baked to different temperatures and demonstrate the efficiency of electron stimulated activation of titanium vacuum chamber.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK038

About •

Received ※ 25 May 2022 — Revised ※ 12 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK039

The Effect of Activation Duration on the Performance of Non-Evaporable Getter Coatings

injection, ECR, experiment, target

2854

E.A. Marshall, O.B. Malyshev, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Non-evaporable getter (NEG) coatings can be activated at temperatures as low as 140°C. However, better pumping properties are achieved using higher temperatures, between 150-300 °C. This paper investigates whether using an increased activation duration can improve the NEG properties obtained using lower activation temperatures, and so decrease the energy and temperature requirement. This could allow a greater range of materials to be used in particle accelerator systems. Our findings have shown that increasing activation duration from 24 hrs to 1 week at 160 °C produces an improvement in the NEG pumping properties.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK039

About •

Received ※ 01 June 2022 — Accepted ※ 10 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK040

Few-Nanosecond Stripline Kickers for Top-Up Injection into PETRA IV

kicker, injection, feedback, synchrotron

2858

G. Loisch, V. Belokurov, F. Obier
DESY, Hamburg, Germany

PETRA IV is the planned ultralow-emittance upgrade of the PETRA III synchrotron light source at DESY, Hamburg. The current baseline injection scheme is an off-axis, top-up injection with few-nanosecond stripline kickers, which would allow for accumulation and least disturbance of experiments during injection. Besides the requirements on kick-strength, field quality, pulse rise-rate, and heat management, two mechanical designs with different apertures are necessary, as the devices will be used for injection and the transverse multi-bunch feedback system. In this contribution we will present the current status of 3D finite element simulations of electromagnetic fields and heating as well as the mechanical design and first pulse electronics tests.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK040

About •

Received ※ 20 May 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 29 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS016

A New Design of PET Cyclotron

cyclotron, proton, acceleration, cavity

2977

O. Karamyshev
JINR, Dubna, Moscow Region, Russia

An innovative approach to a design of cyclotron allows to produce cheaper and more power efficient cyclotrons for medical and industrial application. 15 MeV cyclotron for PET (and other) isotopes production are widely used and in very high demand. In this paper a design of a very compact and cheap to build and to run cyclotron is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS016

About •

Received ※ 08 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 10 July 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS036

HERACLES: A High Average Current Electron Beamline for Lifetime Testing of Novel Photocathodes

cathode, gun, electron, laser

3041

M.B. Andorf, J. Bae, A.C. Bartnik, I.V. Bazarov, J.M. Maxson
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
L. Cultrera
BNL, Upton, New York, USA

Funding: DOE-NP DE-SC0021425 NSF PHY 1549132
We report on the building and commissioning of a high current beamline dedicated to testing novel photocathodes for high current and spin-polarized electron applications. The main features of the beamline are a 200 keV DC electron gun and a beam dump capable of handling 75 kW of beam power. In this report, a Cs3Sb photocathode is used to demonstrate the facilities high current capabilities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS036

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 30 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS053

Proton Beam Irradiation System for Space Part Test

proton, radiation, simulation, target

3093

H.-J. Kwon, J.J. Dang, W.-H. Jung, H.S. Kim, K.Y. Kim, K.R. Kim, S. Lee, Y.G. Song, S.P. Yun
KOMAC, KAERI, Gyeongju, Republic of Korea

Funding: This work is supported by the Nuclear Research and Development Program (2021M2D1A1045615) through the National Research Foundation of Korea.
A proton beam irradiation system for space part test has been developed at Korea Multi-purpose Accelerator Complex (KOMAC) based on 100 MeV proton linac. It consists of a thermal vacuum chamber, a beam diagnostic system and a control system in the low flux beam target room. The thermal vacuum chamber accommodates the capacity for proton beam irradiation in addition to temperature control in vacuum condition. The beam diagnostic system is newly installed to measure the lower dose rate than existing one. In this paper, the proton beam irradiation system for space part test including a thermal vacuum chamber, newly installed beam diagnostic system is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS053

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 17 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS055

Commissioning of the SOCHI Applied Station Beam and Beam Transfer Line at the NICA Accelerator Complex

controls, detector, radiation, booster

3099

A. Slivin, A. Agapov, A.A. Baldin, A.V. Butenko, D.E. Donets, G.A. Filatov, A.R. Galimov, K.N. Shipulin, E. Syresin, A. Tuzikov, V.I. Tyulkin
JINR, Dubna, Moscow Region, Russia
D.V. Bobrovskiy, A.I. Chumakov, S. Soloviev
MEPhI, Moscow, Russia
I.L. Glebov, V.A. Luzanov
GIRO-PROM, Dubna, Moscow Region, Russia
A.S. Kubankin
LPI, Moscow, Russia
A.S. Kubankin
BelSU, Belgorod, Russia
T. Kulevoy, Y.E. Titarenko
ITEP, Moscow, Russia
A.M. Tikhomirov
JINR/VBLHEP, Dubna, Moscow region, Russia

The SOCHI (Station of CHip Irradiation) station was constructed at the NICA accelerator complex for single event effect testing of decapsulated microchips with low-energy ion beams (3.2 MeV/n). The peculiarity of microchip radiation tests in SOCHI is connected with the pulse beam operation of the heavy ion linear accelerator (HILAc) and a restriction on the pulse dose on the target. The SOCHI station construction, the equipment and the results of the first beam runs are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS055

About •

Received ※ 26 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 23 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROXSP3

First Operation of a Klystron Fitted with a Superconducting MgB₂ Solenoid

klystron, solenoid, operation, superconductivity

3138

N. Catalán Lasheras, M. Boronat, G. McMonagle, I. Syratchev
CERN, Meyrin, Switzerland
A. Baig, A. Castilla
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
T. Kimura, P.E. Kolda
CPI, Palo Alto, California, USA
S. Michizono, A. Yamamoto
KEK, Ibaraki, Japan

As part of the effort to reduce the energy consumption of large research facilities using accelerators, high efficiency klystrons are being developed by CERN. However, a large fraction of the wall-plug power required to operate these klystrons is used in the focusing magnetic elements around the klystron in the form of normal conducting solenoids. In 2019, a prototype solenoid made of MgB₂ was manufactured as a joint venture from CERN, Hitachi and KEK with the aim of reducing the power consumption by a factor ten using higher temperature superconductors. The characteristics of the magnet were measured upon manufacture and checked after the transport across the world. In 2020, the MgB₂ magnet was integrated around one of the klystrons in the X-band facility at CERN and put into operation in the beginning of 2021. We present in this paper the final performance of the klystron when fitted with the new SC solenoid and compare it with the standard normal conducting solenoid system.

Slides FROXSP3 [4.661 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-FROXSP3

About •

Received ※ 11 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 16 June 2022

Cite •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)