IPAC2022 - List of Keywords (optics)

Paper	Title	Other Keywords	Page
MOPOST024	A Local Modification of HL-LHC Optics for Improved Performance of the Alice Fixed-Target Layout	target, proton, collimation, experiment	108
	M. Patecki, D. Kikoła Warsaw University of Technology, Warsaw, Poland A.S. Fomin, P.D. Hermes, D. Mirarchi, S. Redaelli CERN, Meyrin, Switzerland
	Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme, grant agreement number 101003442 - FIXEDTARGETLAND. The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) is the world’s largest and most powerful particle accelerator colliding beams of protons and lead ions at energies up to 7 TeV and 2.76 TeV, respectively. ALICE is one of the detector experiments optimised for heavy-ion collisions. A fixed-target experiment in ALICE is considered to collide a portion of the beam halo, split using a bent crystal, with an internal target placed a few meters upstream of the detector. Fixed-target collisions offer many physics opportunities related to hadronic matter and the quark-gluon plasma to extend the research potential of the CERN accelerator complex. Production of physics events depends on the particle flux on target. The machine layout for the fixed-target experiment is being developed to provide a flux of particles on a target high enough to exploit the full capabilities of the ALICE detector acquisition system. In this paper, we discuss a method of increasing the system’s performance by applying a local modification of optics to set the crystal at the optimal betatron phase. marcin.patecki@pw.edu.pl
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST024
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST039	Algorithm to Mitigate Magnetic Hysteresis in Magnets with Unipolar Power Supplies	quadrupole, power-supply, ISAC, cyclotron	156
	J. Nasser, R.A. Baartman, O.K. Kester, S. Kiy, T. Planche, S.D. Rädel, O. Shelbaya TRIUMF, Vancouver, Canada
	Funding: National Research Council Canada The effects of hysteresis on the fields produced by magnetic lenses are not accounted for in TRIUMF’s models of the accelerators. Under certain conditions, such as quadrupoles with unipolar power supplies operating at low currents, these effects have introduced significant field errors with consequences upon tranverse tunes. To combat these uncertainties and make the fields more reproducible and stable, a technique new to TRIUMF has been implemented. This technique ramps the current cyclically about the desired setpoint to reach a reproducible field that is independent of its history. Results of magnetic measurements at TRIUMF using this technique are presented, as well as the expected improvements to the accuracy of the beam optics model, particularly for unipolar quadrupoles.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST039
About •	Received ※ 03 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOST041	Dynamic Aperture Studies for the Transfer Line From FLUTE to cSTART	storage-ring, quadrupole, simulation, linac	164
	J. Schäfer, B. Härer, A.-S. Müller, A.I. Papash, R. Ruprecht, M. Schuh KIT, Karlsruhe, Germany
	Funding: J. Schäfer acknowledges the support by the DFG- funded Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology". The compact STorage ring for Accelerator Research and Technology cSTART project will deliver a new KIT accelerator test facility for the application of novel acceleration techniques and diagnostics. The goal is to demonstrate storing an electron beam of a Laser Plasma Accelerator (LPA) in a compact circular accelerator for the first time. Before installing an LPA, the Far-Infrared Linac and Test Experiment (FLUTE) will serve as a full energy injector for the compact storage ring, providing stable bunches with a length down to a few femtoseconds. The transport of the bunches from FLUTE to the cSTART storage ring requires a transfer line which includes horizontal, vertical and coupled deflections which leads to coupling of the dynamics in the two transverse planes. In order to realize ultra-short bunch lengths at the end of the transport line, it relies on special optics which invokes high and negative dispersion. This contribution presents dynamic aperture studies based on six-dimensional tracking through the lattice of the transfer line.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST041
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT020	Longitudinal Phase Space Diagnostics with Corrugated Structure at the European XFEL	electron, diagnostics, FEL, laser	275
	S. Tomin, W. Decking, N. Golubeva, A.I. Novokshonov, T. Wohlenberg, I. Zagorodnov DESY, Hamburg, Germany
	Characterization of the longitudinal phase space (LPS) of the electron beam after the FEL process is important for its study and tuning. At the European XFEL, a single plate corrugated structure was installed after the SASE2 undulator to measure the LPS of the electron beam. The beam passing near the plate’s corrugations creates wakefields, which induce a correlation between time and the transverse distribution of the beam. The longitudinal phase space of the beam is then analyzed on a scintillating screen monitor placed in the dispersion section. In this paper, we present the result of commissioning the corrugated structure and the first LPS measurement.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT020
About •	Received ※ 12 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT031	Renovation of the SR Beam Profile Monitors with Novel Polycrystalline Diamond Mirrors at the SuperKEKB Accelerator	extraction, laser, radiation, synchrotron	313
	G. Mitsuka, H. Ikeda, T.M. Mitsuhashi KEK, Ibaraki, Japan
	SR beam profile monitors are fundamental to perform the stable beam operation of SuperKEKB. To suppress thermal deformation of SR extraction mirrors–a long-standing issue in SR monitors–, we developed platinum coated diamond mirrors in 2019. The diamond mirrors are made with optical-quality polycrystal-diamond-substrate with extremely large thermal conductivity, and have a size of 20 mm (W) x 30 mm (H) x 2 mm (D). Surface flatness better than λ/5 was observed in an optical testing with a laser interferometer. The diamond mirrors have been installed in HER and LER in 2020 summer and 2021 summer, respectively. Through irradiation for an year at the beam current greater than 800 mA, no significant deformation of the diamond mirrors has been observed. In this talk, we will discuss the design, construction, and optical testing of the polycrystal diamond mirrors. Also beam measurements performed using an interferometer, a coronagraph, a streak camera, and a fast gate camera will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT031
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 02 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOPT047	Experimental Demonstration of Machine Learning Application in LHC Optics Commissioning	quadrupole, MMI, simulation, diagnostics	359
	E. Fol, F.S. Carlier, J. Dilly, M. Hofer, J. Keintzel, M. Le Garrec, E.H. Maclean, T.H.B. Persson, F. Soubelet, R. Tomás García, A. Wegscheider CERN, Meyrin, Switzerland J.F. Cardona UNAL, Bogota D.C, Colombia
	Recently, we conducted successful studies on the suitability of machine learning (ML) methods for optics measurements and corrections, incorporating novel ML-based methods for local optics corrections and reconstruction of optics functions. After performing extensive verifications on simulations and past measurement data, the newly developed techniques became operational in the LHC commissioning 2022. We present the experimental results obtained with the ML-based methods and discuss future improvements. Besides, we also report on improving the Beam Position Monitor (BPM) diagnostics with the help of the anomaly detection technique capable to identify malfunctioning BPMs along with their possible fault causes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT047
About •	Received ※ 07 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 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, vacuum, experiment, 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)

MOPOTK002	Fast Orbit Response Matrix Measurement via Sine-Wave Excitation of Correctors at Sirius	storage-ring, synchrotron, quadrupole, lattice	425
	M.M.S. Velloso, M.B. Alves, F.H. de Sá LNLS, Campinas, Brazil
	Sirius is the new 4th generation storage ring based synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS). In this work, we report on the implementation at Sirius of a fast method for orbit response matrix (ORM) measurement which is based on sine-wave parallel excitation of orbit corrector magnets’ strength. This ‘‘AC method" has reduced the ORM measurement time from ∼ 25 minutes to 2.5-3 minutes and displayed increased precision if compared to the standard serial measurement procedure. When used as input to the Linear Optics from Closed Orbits (LOCO) correction algorithm, the AC ORM yielded similar optics corrections with less aggressive quadrupoles strength changes.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK002
About •	Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK004	Status of the Soleil Upgrade Lattice Robustness Studies	lattice, injection, MMI, simulation	433
	O.R. Blanco-García INFN/LNF, Frascati, Italy D. Amorim, A. Loulergue, L.S. Nadolski, R. Nagaoka SOLEIL, Gif-sur-Yvette, France M.A. Deniaud JAI, Egham, Surrey, United Kingdom
	The SOLEIL synchrotron has entered its Technical Design Report (TDR) phase for the upgrade of its storage ring to a fourth generation synchrotron light source. Verification of the equipment specifications (alignment, magnets, power supplies, BPMs), and the methodology for optics corrections are critical in order to ensure the feasibility of rapid commissioning restoring full performance for daily operations. The end-to-end simulation, from beam threading in the first turns to beam storage and stacking, should be handled with a comprehensive model close to the actual commissioning procedure, taking into account all practical steps. During 2021 and 2022, the CDR lattice has undergone significant modifications in response to additional constraints. In this paper, we present an update of the robustness studies for the TDR baseline lattice.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK004
About •	Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK006	Off-Energy Operation for the ESRF-EBS Storage Ring	SRF, injection, sextupole, lattice	437
	L. Hoummi, T. Brochard, N. Carmignani, L.R. Carver, J. Chavanne, S.M. Liuzzo, T.P. Perron, R. Versteegen, S.M. White ESRF, Grenoble, France P. Raimondi SLAC, Menlo Park, California, USA
	The ESRF-EBS is the first 4th generation source making use of the Hybrid Multi-Bend Achromat (HMBA) lattice cell, reaching an equilibrium horizontal emittance of 140 pm.rad in user mode (insertion devices (ID) gaps open). The injection in the storage ring (SR) is conducted with a short booster, operated off-energy. The RF frequency is increased compared to the nominal one to put the beam on a dispersive orbit, thus going off-axis in quadrupoles. The induced dipolar feed down effects reduce the booster horizontal emittance. The same strategy is extended to the ESRF-EBS SR, for an expected emittance reduction of about 20 pm.rad. A first approach shifts the RF frequency by +300 Hz to operate at -1% energy offset. Optimal quadrupole and sextupole settings are defined for this off-energy operation based on simulations. The settings are then tested in the SR in terms of dynamic aperture and injection efficiency.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK006
About •	Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK013	Machine Learning Based Surrogate Model Construction for Optics Matching at the European XFEL	simulation, quadrupole, electron, FEL	461
	Z.H. Zhu, Y. Chen, W. Qin, M. Scholz, S. Tomin DESY, Hamburg, Germany
	Beam optics matching is a daily routine in the operation of an X-ray free-electron laser facility. Usually, linear optics is employed to conduct the beam matching in the control room. However, the collective effects like space charge dominate the electron bunch in the low-energy region which decreases the accuracy of the existing tool. Therefore, we proposed a scheme to construct a surrogate model with nonlinear optics and collective effects to speed up the optics matching in the European XFEL injector section. This model also facilitates further research on beam dynamics for the space-charge dominated beam.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK013
About •	Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK014	Optics of a Recirculating Beamline for MESA	experiment, target, injection, scattering	465
	C.P. Stoll, A. Meseck KPH, Mainz, Germany
	The Mainz Energy-recovering Superconducting Accelerator (MESA) is an Energy Recovery Linac (ERL) facility under construction at the Johannes Gutenberg-University in Mainz. It provides the opportunity for precision physics experiments with a 1 mA c.w. electron beam in its initial phase. In this phase experiments with unpolarised, high-density 10¹⁹ atoms per cm² gas jet targets are foreseen at the Mainz Gas Internal Target Experiment (MAGIX). To allow experiments with thin polarised gas targets with sufficiently high interaction rates in a later phase, the beam current must be increased to up to 100 mA, which would pose significant challenges to the existing ERL machine. Thus, it is proposed here to use MESA in pulsed operation with a repetition rate of several kHz to fill a recirculating beamline, providing a quasi c.w. beam current to a thin gas target. The optics necessary for this recirculating beamline are presented here.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK014
About •	Received ※ 01 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK028	Zero Dispersion Optics to Improve Horizontal Emittance Measurements at the CERN Proton Synchrotron	emittance, quadrupole, simulation, space-charge	503
	W. Van Goethem, F. Antoniou, F. Asvesta, H. Bartosik, A. Huschauer CERN, Meyrin, Switzerland
	In modern particle accelerators, the horizontal dispersion function is forced to zero at locations with instrumentation measuring the transverse beam distribution, in order to remove the dispersive contribution to the horizontal beam size. The design of the CERN Proton Synchrotron did not foresee such a zero-dispersion insertion, making it challenging to get a good precision on the beam size measurements. In this contribution, we present a new optics configuration, which allows to reach zero horizontal dispersion at the locations of different beam size measurement locations. This can be achieved by powering a set of trim quadrupoles, the so-called Low Energy Quadrupoles (LEQ). We investigate how the resulting optics perturbation affects beam parameters.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK028
About •	Received ※ 07 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 08 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK029	Improved Low-Energy Optics Control for Transverse Emittance Preservation at the CERN Proton Synchrotron	emittance, space-charge, quadrupole, lattice	507
	W. Van Goethem, F. Antoniou, F. Asvesta, H. Bartosik, A. Huschauer CERN, Meyrin, Switzerland
	Preservation of the transverse emittances across the CERN accelerator chain is an important requirement for beams produced for the Large Hadron Collider (LHC). In the CERN Proton Synchrotron (PS), high brightness LHC-type beams are stored on a long flat bottom for up to 1.2 seconds. During this storage time, direct space charge effects may lead to resonance crossing and subsequent growth of the transverse emittances. Previous studies showed an important emittance increase when the PS working point is moved near integer tune values. Subsequent simulation studies confirmed that this observation is caused by an interplay of space charge effects and the optics beatings induced by the Low Energy Quadrupoles (LEQ). A new optics configuration using these quadrupoles to reduce the optics beating and the emittance growth was developed and experimentally validated. The results of simulation and experimental studies are presented in this contribution.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK029
About •	Received ※ 07 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK032	An N-BPM Momentum Reconstruction for Linear Transverse Coupling Measurements in LHC and HL-LHC	coupling, lattice, resonance, controls	519
	A. Wegscheider, R. Tomás García CERN, Meyrin, Switzerland
	The measurement and control of linear transverse coupling is important for the operation of an accelerator. The calculation of the linear transverse coupling resonance driving terms (RDTs) ’1001 and ’1010 relies on the complex spectrum of the turn-by-turn motion. To obtain the complex signal, a reconstruction of the particle motion is needed. For this purpose, the signal of a second BPM with a suitable phase shift is usually used. In this work, we explore the possibility of including more BPMs in the reconstruction of the transverse momentum, which could reduce the effects of statistical errors and systematic uncertainties. This, in turn, could improve the precision and accuracy of the RDTs, which could be of great benefit for locations where an exact knowledge of the transverse coupling or other RDTs is important. We present the development of a new method to reconstruct the particle’s momentum that uses a statistical analysis of several nearby BPMs. The improved precision is demonstrated via simulations of LHC and HL-LHC lattices.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK032
About •	Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK036	Studies of the Vertical Excursion Fixed Field Alternating Gradient Accelerator	lattice, closed-orbit, quadrupole, simulation	535
	M.E. Topp-Mugglestone, S.L. Sheehy JAI, Oxford, United Kingdom J.-B. Lagrange, S. Machida STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The Vertical Excursion Fixed Field Alternating Gradient Accelerator (VFFA) concept offers a number of advantages over existing accelerator archetypes, as discussed in previous works. However, the VFFA has nonplanar orbits by design and unavoidable transverse coupling. Hence, current understanding of the dynamics of this machine is limited; this paper presents some in-depth study of its behaviour using a combination of analytical and numerical techniques.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK036
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK037	Impact of Insertion Devices on Diamond-II Lattice	insertion, insertion-device, emittance, lattice	539
	B. Singh, R.T. Fielder, H. Ghasem, J. Kallestrup, I.P.S. Martin, T. Olsson DLS, Oxfordshire, United Kingdom
	Funding: DLS ltd The DIAMOND-II lattice is based on the ESRF-EBS cell, with the centre dipole replaced by a (chromatic) mid-straight, and a -I transformer, higher order achromat (HOA) & dispersion bumps to control the nonlinear dynamics. The majority of insertion devices currently on operation in Diamond will be either retained or upgraded as part of the Diamond-II program, and the new mid straights allow the total number of ID beamlines to be increased from 28 to 36.Therefore, it is important to investigate how IDs will affect the emittance, energy spread and linear and nonlinear beam dynamics. The kickmap approach has been used to model all IDs, including APPLE-II and APPLE-II Knot with active shim wires. In this paper, the outcome of these investigations will be presented and discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK037
About •	Received ※ 04 June 2022 — Accepted ※ 30 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK038	BPM Analysis with Variational Autoencoders	network, focusing, diagnostics, GPU	543
	C.C. Hall, J.P. Edelen, J.A. Einstein-Curtis, M.C. Kilpatrick RadiaSoft LLC, Boulder, Colorado, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics under Award Number DE-SC0021699. In particle accelerators, beam position monitors (BPMs) are used extensively as a non-intercepting diagnostic. Significant information about beam dynamics can often be extracted from BPM measurements and used to actively tune the accelerator. However, common measurement tools, such as measurements of kicked beams, may become more difficult when very strong nonlinearities are present or when data is very noisy. In this work, we examine the use of variational autoencoders (VAEs) as a technique to extract measurements of the beam from simulated turn-by-turn BPM data. In particular, we show that VAEs may have the possibility to outperform other dimensionality reduction techniques that have historically been used to analyze such data. When the data collection period is limited, or the data is noisy, VAEs may offer significant advantages.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK038
About •	Received ※ 09 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK046	Design Concept for a Second Interaction Region for the Electron-Ion Collider	electron, hadron, collider, detector	564
	B.R. Gamage, V. Burkert, R. Ent, Y. Furletova, D.W. Higinbotham, T.J. Michalski, R. Rajput-Ghoshal, D. Romanov, T. Satogata, A. Seryi, C. Weiss, W. Wittmer, Y. Zhang JLab, Newport News, Virginia, USA E.C. Aschenauer, J.S. Berg, K.A. Drees, A. Jentsch, A. Kiselev, C. Montag, R.B. Palmer, B. Parker, V. Ptitsyn, F.J. Willeke, H. Witte BNL, Upton, New York, USA C. Hyde ODU, Norfolk, Virginia, USA F. Lin, V.S. Morozov ORNL RAD, Oak Ridge, Tennessee, USA P. Nadel-Turonski SBU, Stony Brook, New York, USA
	Funding: Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177, Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and UT-Battelle, LLC, under contract No. DE-AC05-00OR22725 In addition to the day-one primary Interaction Region (IR), the design of the Electron Ion Collider (EIC) must support operation of a 2nd IR potentially added later. The 2nd IR is envisioned in an existing experimental hall at RHIC IP8, compatible with the same beam energy combinations as the 1st IR over the full center of mass energy range of ~20 GeV to ~140 GeV. The 2nd IR is designed to be complementary to the 1st IR. In particular, a secondary focus is added in the forward ion direction of the 2nd IR hadron beamline to optimize its capability in detecting particles with magnetic rigidities close to those of the ion beam. We provide the current design status of the 2nd IR in terms of parameters, magnet layout and beam dynamics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK046
About •	Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK050	Linac Optics Optimization with Multi-Objective Optimization	linac, lattice, quadrupole, controls	572
	I. Neththikumara, T. Satogata ODU, Norfolk, Virginia, USA R.M. Bodenstein, S.A. Bogacz, T. Satogata JLab, Newport News, Virginia, USA A. Vandenhoeke ULB, Bruxelles, Belgium
	Funding: This material is based upon work supported by the U.S. Department of Energy under contract DE-AC05-06OR23177. The beamline design of recirculating linacs requires special attention to avoid beam instabilities due to RF wakefields. A proposed high-energy, multi-pass energy recovery demonstration at CEBAF uses a low beam current. Stronger focusing at lower energies is necessary to avoid beam breakup(BBU) instabilities, even with this small beam current. The CEBAF linac optics optimization balances over-focusing at higher energies and beta excursions at lower energies. Using proper mathematical expressions, linac optics optimization can be achieved with evolutionary algorithms. Here, we present the optimization process of North Linac optics using multi-objective optimization.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK050
About •	Received ※ 31 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOTK053	RLAs with FFA Arcs for Protons and Electrons	cavity, linac, SRF, hadron	584
	V.S. Morozov ORNL RAD, Oak Ridge, Tennessee, USA J.F. Benesch, R.M. Bodenstein, S.A. Bogacz, A. Coxe, K.E. Deitrick, D. Douglas, B.R. Gamage, G.A. Krafft, K.E.Price. Price, Y. Roblin, A. Seryi JLab, Newport News, Virginia, USA J.S. Berg, S.J. Brooks, F. Méot, D. Trbojevic BNL, Upton, New York, USA D. Douglas Douglas Consulting, York, Virginia, USA G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Authored in part by UT-Battelle, LLC, Jefferson Science Associates, LLC, and Brookhaven Science Associates, LLC under Contracts DE-AC05-00OR22725, DE-AC05-06OR23177, and DE-SC0012704 with the US DOE. Recirculating Linear Accelerators (RLAs) provide an efficient way of producing high-power, high-quality, continuous-wave hadron and lepton beams. However, their attractiveness had been limited by the cumbersomeness of multiple recirculating arcs and by the complexity of the spreader and recombiner regions. The latter problem sets one of the practical limitations on the maximum number of recirculations. We present an RLA design concept where the problem of multiple arcs is solved using the Fixed-Field Alternating gradient (FFA) design as in CBETA. The spreader/recombiner design is greatly simplified using an adiabatic matching approach. It allows for the spreader/recombiner function to be accomplished by a single beam line. The concept is applied to the designs of a high-power hadron accelerator being considered at ORNL and a CEBAF electron energy doubling project, FFA@CEBAF, being developed at Jefferson lab.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK053
About •	Received ※ 10 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)

TUOZSP1	Prospects for Optics Measuements in FCC-ee	damping, dipole, collider, radiation	827
	J. Keintzel, R. Tomás García, F. Zimmermann CERN, Meyrin, Switzerland
	Within the framework of the Future Circular Collider Feasibility Study, the design of the electron-positron collider FCC-ee is optimised, as a possible future double collider ring, currently foreseen to start operation during the 2040s. With close to 100 km of circumference and strong synchrotron radiation damping at highest beam energy, adequate beam measurements are needed to control the optics at the desired level. Various possible techniques to measure the optics in FCC-ee are explored, including the option of turn-by-turn measurements in combination with an AC-dipole.
	Slides TUOZSP1 [2.738 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOZSP1
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS006	FILO: A New Application to Correct Optics in the ESRF-EBS Storage Ring	SRF, quadrupole, lattice, operation	1401
	S.M. Liuzzo, N. Carmignani, L.R. Carver, L. Farvacque, L. Hoummi, T.P. Perron, B. Roche, B. Vedder, S.M. White ESRF, Grenoble, France
	A new optics correction application (Fit and Improvement of Linear Optics, FILO) was designed and set in place for the ESRF-EBS storage ring. The widely used software LOCO* is not available at ESRF and despite a few trials to set it in operation, it has been decided to write a new code. The application is flexible, may be used via the control system simulators and is adapted to a user friendly operation thanks to a wizard mode. Some features of LOCO are copied over, some others are yet to be implemented. The measurement of on and off-energy response matrices using slow or fast steerers is integrated in the same application. Results obtained with this application are presented together with an overview of the future developments. *J Safranek, Experimental determination of storage ring optics using orbit response measurements, https://doi.org/10.1016/S0168-9002(97)00309-4
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS006
About •	Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS008	Lifetime Correction Using Fast-Off-Energy Response Matrix Measurements	sextupole, simulation, lattice, operation	1409
	S.M. Liuzzo, N. Carmignani, L.R. Carver, L. Hoummi, T.P. Perron, B. Roche, S.M. White ESRF, Grenoble, France
	Following the measurements done at MAX-IV * we try to exploit for the ESRF-EBS Storage Ring (SR) off-energy response matrix measurement for the optimization of Touschek lifetime. The measurements performed with fast AC steerers on- and off-energy are analyzed and fitted producing an effective model including quadrupole and sextupole errors. Several alternatives to extrapolate sextupoles strengths for correction are compared in terms of lifetime. For the time being none of the corrections could produce better lifetime than the existing empirically optimized set of sextupoles. *D.Olsson et al., Nonlinear optics from off-energy closed orbits, 10.1103/PhysRevAccelBeams.23.102803
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS008
About •	Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPOMS018	Error Analysis and Commissioning Simulation for the PETRA-IV Storage Ring	lattice, simulation, MMI, storage-ring	1442
	T. Hellert, I.V. Agapov, S.A. Antipov, R. Bartolini, R. Brinkmann, Y.-C. Chae, D. Einfeld, M.A. Jebramcik, J. Keil DESY, Hamburg, Germany
	The upgrade of the PETRA-III storage ring into a diffraction limited synchrotron radiation source is nearing the end of its detailed technical design phase. We present a preliminary commissioning simulation for PETRA-IV demonstrating that the final corrected machines meet the performance design goals.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS018
About •	Received ※ 10 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST008	Optics Correction Strategy for Run 3 of the LHC	coupling, MMI, injection, quadrupole	1687
	T.H.B. Persson, F.S. Carlier, A. Costa Ojeda, J. Dilly, V. Ferrentino, E. Fol, H. García Morales, M. Hofer, E.J. Høydalsvik, J. Keintzel, M. Le Garrec, E.H. Maclean, L. Malina, F. Soubelet, R. Tomás García, A. Wegscheider, L. van Riesen-Haupt CERN, Meyrin, Switzerland J.F. Cardona UNAL, Bogota D.C, Colombia
	After almost 4 years of shutdown the LHC is again operational in 2022. Experience from the previous Long Shutdown (LS) has shown that the local errors around the triplet magnets changed significantly and it is likely we will again see different errors in 2022. In the LHC there is an interplay between the linear and the nonlinear correction which can make the corrections difficult and time-consuming to find. In this article, we describe the measurements and corrections performed during the commissioning in 2022 in order to control both the linear and the nonlinear optics to high precision.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST008
About •	Received ※ 08 June 2022 — Revised ※ 25 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST011	Studies on Top-Up Injection into the FCC-ee Collider Ring	injection, kicker, collider, lattice	1699
	P.J. Hunchak, M.J. Boland CLS, Saskatoon, Saskatchewan, Canada M. Aiba PSI, Villigen PSI, Switzerland W. Bartmann, Y. Dutheil, M. Hofer, R.L. Ramjiawan, F. Zimmermann CERN, Meyrin, Switzerland M.J. Boland University of Saskatchewan, Saskatoon, Canada
	In order to maximize the luminosity production time in the FCC-ee, top-up injection will be employed. The positron and electron beams will be accelerated to the collision energy in the booster ring before being injected with either a small transverse or longitudinal separation to the stored beam. Using this scheme essentially keeps the beam current constant and, apart from a brief period during the injection process, collision data can be continuously acquired. Two top-up injection schemes, each with on- and off-momentum sub-schemes, viable for FCC-ee have been identified in the past and are studied in further detail to find a suitable design for each of the four operation modes of the FCC-ee. In this paper, injection straight optics, initial injection tracking studies and the effect on the stored beam are presented. Additionally, a basic proxy error lattice is introduced as a first step to studying injection into an imperfect machine.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST011
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST015	Implementation of a Tune Sweep Slow Extraction with Constant Optics at MedAustron	extraction, simulation, betatron, operation	1715
	P.A. Arrutia Sota, M.A. Fraser, B. Goddard, V. Kain, F.M. Velotti CERN, Meyrin, Switzerland P. Burrows JAI, Oxford, United Kingdom A. De Franco QST Rokkasho, Aomori, Japan F. Kuehteubl, M.T.F. Pivi, D.A. Prokopovich EBG MedAustron, Wr. Neustadt, Austria
	Conventional slow extraction driven by a tune sweep perturbs the optics and changes the presentation of the beam separatrix to the extraction septum during the spill. The constant optics slow extraction (COSE) technique, recently developed and deployed operationally at the CERN Super Proton Synchrotron to reduce beam loss on the extraction septum, was implemented at MedAustron to facilitate extraction with a tune sweep of operational beam quality. COSE fixes the optics of the extracted beam by scaling all machine settings with the beam rigidity following the extracted beam’s momentum. In this contribution the implementation of the COSE extraction technique is described before it is compared to the conventional tune sweep and operational betatron core driven cases using both simulations and recent measurements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST015
About •	Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST017	Design of a Collimation Section for the FCC-ee	collimation, collider, operation, quadrupole	1722
	M. Hofer, A. Abramov, R. Bruce, K. Oide, F. Zimmermann CERN, Meyrin, Switzerland M. Moudgalya, T. Pieloni EPFL, Lausanne, Switzerland K. Oide KEK, Ibaraki, Japan
	The design parameters of the FCC-ee foresee operation with a total stored beam energy of about 20 MJ, exceeding those of previous lepton colliders by almost two orders of magnitude. Given the inherent damage potential, a halo collimation system is studied to protect the machine hardware, in particular superconducting equipment such as the final focus quadrupoles, from sudden beam loss. The different constraints that led to dedicating one straight section to collimation will be outlined. In addition, a preliminary layout and optics for a collimation insertion are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST017
About •	Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 25 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST023	Design of a Very Low Energy Beamline for NA61/SHINE	experiment, target, detector, radiation	1741
	C.A. Mussolini, N. Charitonidis CERN, Meyrin, Switzerland P. Burrows, C.A. Mussolini JAI, Oxford, United Kingdom P. Burrows, C.A. Mussolini Oxford University, Physics Department, Oxford, Oxon, United Kingdom Y. Nagai Colorado University at Boulder, Boulder, Colorado, USA E.D. Zimmerman CIPS, Boulder, Colorado, USA
	A new, low-energy branch is being designed for the H₂ beamline at the CERN North Experimental Area. This new low-energy branch would extend the capabilities of the current infrastructure enabling the study of particles in the low, 1 - 13 GeV/c, momentum range. The first experiment to profit from this new line will be NA61/SHINE (SPS Heavy Ion and Neutrino Experiment), a multi-purpose experiment studying hadron production in hadron-proton, hadron-nucleus and nucleus-nucleus collisions at the SPS. However, other future fixed target experiments or test-beam experiments installed in the downstream zones could also benefit from the low-energy particles provided. The proposed layout and expected performance of this line, along with estimates of particle rates, and considerations on the technical implementation of the beamline are presented in this contribution. A description on the instrumentation, which will enable particle-by-particle tagging, crucial for the experiments scope, is also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST023
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 29 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOST024	Physics Beyond Colliders: The Conventional Beams Working Group	experiment, proton, kaon, target	1745
	C.A. Mussolini, D. Banerjee, A. Baratto Roldan, J. Bernhard, M. Brugger, N. Charitonidis, G.L. D’Alessandro, L. Gatignon, A. Gerbershagen, F. Metzger, R.P. Murphy, E.G. Parozzi, S.M. Schuh-Erhard, F.W. Stummer, M.W.U. Van Dijk CERN, Meyrin, Switzerland F. Metzger HISKP, Bonn, Germany R.P. Murphy, F.W. Stummer Royal Holloway, University of London, Surrey, United Kingdom C.A. Mussolini, F.W. Stummer JAI, Oxford, United Kingdom C.A. Mussolini Oxford University, Physics Department, Oxford, Oxon, United Kingdom E.G. Parozzi Universita Milano Bicocca, MILANO, Italy E.G. Parozzi INFN MIB, MILANO, Italy
	The Physics Beyond Colliders initiative aims to exploit the full scientific potential of the CERN accelerator complex and its scientific infrastructure for particle physics studies, complementary to current and future collider experiments. Several experiments have been proposed to fully utilize and further advance the beam options for the existing fixed target experiments present in the North and East Experimental Areas of the CERN SPS and PS accelerators. We report on progress with the RF-separated beam option for the AMBER experiment, following a recent workshop on this topic. In addition we cover the status of studies for ion beams for the NA⁶⁰⁺ experiment, as well as of those for high intensity beams for Kaon physics and feebly interacting particle searches. With first beams available in 2021 after a CERN-wide long shutdown, several muon beam options were already tested for the NA64mu, MUonE and AMBER experiments.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST024
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 10 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT007	First Interaction Region Local Coupling Corrections in the LHC Run 3	coupling, quadrupole, MMI, experiment	1838
	F. Soubelet, T.H.B. Persson, R. Tomás García CERN, Meyrin, Switzerland Ö. Apsimon, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: This research is supported by the LIV. DAT Center for Doctoral Training, STFC and the European Organization for Nuclear Research The successful operation of large scale particle accelerators depends on the precise correction of unavoidable magnetic field or magnet alignment errors present in the machine. During the LHC Run 2, local linear coupling in the interaction regions (IR) was shown to have a significant impact on the beam size, making its proper handling a necessity for Run 3 and the High Luminosity LHC (HL-LHC). A new approach to accurately minimise the local IR linear coupling based on correlated external variables such as the \|C-\| had been proposed, which relies on the application of a rigid waist shift in order to create an asymmetry in the IR optics. In this contribution, preliminary corrections from the 2021 beam test and the early 2022 commissioning are presented, as well as first results of the new method’s experimental configuration tests in the LHC Run 3 commissioning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT007
About •	Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT008	Supervised Machine Learning for Local Coupling Sources Detection in the LHC	coupling, quadrupole, network, simulation	1842
	F. Soubelet, T.H.B. Persson, R. Tomás García CERN, Meyrin, Switzerland Ö. Apsimon, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: This research is supported by the LIV. DAT Center for Doctoral Training, STFC and the European Organization for Nuclear Research Local interaction region (IR) linear coupling in the LHC has been shown to have a negative impact on beam size and luminosity, making its accurate correction for Run 3 and beyond a necessity. In view of determining corrections, supervised machine learning has been applied to the detection of linear coupling sources, showing promising results in simulations. An evaluation of different applied models is given, followed by the presentation of further possible application concepts for linear coupling corrections using machine learning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT008
About •	Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 29 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT010	Progress on Action Phase Jump for LHC Local Optics Correction	simulation, quadrupole, operation, interaction-region	1850
	J.F. Cardona, Y. Rodriguez Garcia UNAL, Bogota D.C, Colombia H. García Morales, M. Hofer, E.H. Maclean, T.H.B. Persson, R. Tomás García CERN, Meyrin, Switzerland Y. Rodriguez Garcia UAN, Bogotá D.C., Colombia
	The correction of the local optics at the Interaction Regions of the LHC is crucial to ensure a good performance of the machine. This is even more important for the future LHC upgrade, HL-LHC, where the optics is more sensitive to magnetic errors. For that reason, it is important to explore alternative techniques for local optics corrections. In this paper, we evaluate the performance of the Action Phase Jump method for optics correction in the LHC and the HL-LHC and explore ways to integrate this technique in regular operations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT010
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT012	MAD-X for Future Accelerators	coupling, closed-orbit, GUI, simulation	1858
	T.H.B. Persson, H. Burkhardt, R. De Maria, L. Deniau, E.J. Høydalsvik, A. Latina, P.K. Skowroński, R. Tomás García, L. van Riesen-Haupt CERN, Meyrin, Switzerland
	The development of MAD-X was started more than 20 years ago and it still remains the main tool for single particle dynamics for both optics design, error studies as well as for operational model-based software at CERN. In this article, we outline some of the recent development of MAD-X and plans for the future. In particular, we focus on the development of the twiss module used to calculate optics functions in MAD-X which is based on first and second order matrices. These have traditionally been calculated as an expansion around the ideal orbit. In this paper, we describe explicitly how an expansion around the closed orbit can be employed instead, in order to get more precise results. We also describe the latest development of the beam-beam long range wire compensator in MAD-X, an element that has been implemented using the aforementioned approach.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT012
About •	Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT016	Beam-Based Reconstruction of the Shielded Quench-Heater Fields for the LHC Main Dipoles	dipole, shielding, operation, injection	1874
	L.C. Richtmann, L. Bortot, E. Ravaioli, C. Wiesner, D. Wollmann CERN, Meyrin, Switzerland
	Small orbit oscillations of the circulating particle beams have been observed immediately following quenches in the LHC’s superconducting main dipole magnets. Magnetic fields generated during the discharge into the quench heaters were identified as the cause. Since the resulting, shielded field inside the beam screen cannot be measured in-situ, the time evolution of the field has to be reconstructed from the measured beam excursions. In this paper, the field-reconstruction method using rotation in normalized phase space and the optimized fitting algorithm are described. The resulting rise times and magnetic field levels are presented for quench events that occurred during regular operation as well as for dedicated beam experiments. Finally, different approaches to model the shielding behavior of the beam screen are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT016
About •	Received ※ 16 May 2022 — Accepted ※ 13 June 2022 — Issue date ※ 26 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT017	First Optics Design for a Transverse Monochromatic Scheme for the Direct S-Channel Higgs Production at FCC-ee Collider	collider, positron, luminosity, site	1878
	H.P. Jiang Harbin Institute of Technology (HIT) , Harbin, People’s Republic of China A. Faus-Golfe, Z.D. Zhang Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France K. Oide KEK, Ibaraki, Japan Z.D. Zhang IHEP, Beijing, People’s Republic of China Z.D. Zhang UCAS, Beijing, People’s Republic of China F. Zimmermann CERN, Meyrin, Switzerland
	The FCC-ee collider baseline foresees four different energy operation modes: Z, WW, H(ZH) and ttbar. An optional fifth mode, called s-channel Higgs production mode, could allow the measurement of the electron Yukawa coupling, in dedicated runs at 125 GeV centre-of-mass energy, provided that the centre-of-mass energy spread, can be reduced by at least an order of magnitude (5-10 MeV). The use of a special collision technique: a monochromatization scheme is one way to accomplish it. There are several methods to implement a monochromatization scheme. One method, named transverse monochromatization scheme, consists of introducing a dispersion different from zero but opposite sign for the two colliding beams at the Interaction Point (IP); In this paper we will report about the first attempt to design a new optics to implement a transverse monochromatic scheme for the FCC-ee Higgs production totally compatible with the standard mode of operation without dispersion at the IP.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT017
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT019	RHIC Blue Snake Blues	polarization, closed-orbit, operation, simulation	1881
	F. Méot, E.C. Aschenauer, H. Huang, A. Marusic, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, V. Schoefer BNL, Upton, New York, USA
	Funding: Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Two helical full snakes are used in both Blue and Yellow rings of RHIC collider, in order to preserve beam polarization during acceleration to collision energy and polarization lifetime at store. A snake in RHIC is comprised of four 2.4m long modules, powered by pair. During the startup of RHIC Run 22 in December 2021, two successive power dips have caused the 9 o’clock RHIC BlBrookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.ue ring snake to loose two of its four modules. In spite of this regrettable loss, it has been possible to maintain near 180deg snake precession, by proper powering of the remaining two modules, as well as, by re-tuning the 3 o’clock sister snake, vertical spin precession axis around the ring and spin tune 1/2. Determining these new settings, in order to salvage polarization with the handicapped Blue snake pair, has required series of numerical simulations, a brief overview is given here.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT019
About •	Received ※ 03 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT035	Optics for Strong Hadron Cooling in EIC HSR-IR2	electron, hadron, kicker, cavity	1920
	S. Peggs, W.F. Bergan, D. Bruno, Y. Gao, D. Holmes, R.F. Lambiase, C. Liu, H. Lovelace III, G.J. Mahler, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, E. Wang, D. Weiss, D. Xu BNL, Upton, New York, USA S.V. Benson, T.J. Michalski JLab, Newport News, Virginia, USA F. Micolon Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC001 2704, and by Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177. Insertion Region 2 (IR2) of the Relativistic Heavy Ion Collider will be modified to accommodate a Strong Hadron Cooling facility in the Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC). This paper describes the current proof-of-principle design of HSR-IR2 - layout, optical performance, design methodology, and engineering requirements. It also describes the challenges and opportunities in the future development of the HSR-IR2 design, in order to further optimize Strong Hadron Cooling performance.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT035
About •	Received ※ 02 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 06 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT043	Dynamic Aperture of the EIC Electron Storage Ring	sextupole, lattice, quadrupole, electron	1950
	Y.M. Nosochkov, Y. Cai SLAC, Menlo Park, California, USA J.S. Berg, J. Kewisch, Y. Li, D. Marx, C. Montag, S. Tepikian, H. Witte BNL, Upton, New York, USA G.H. Hoffstaetter, J.E. Unger Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by the Department of Energy Contract DE-AC02-76SF00515, by Brookhaven Science Associates, LLC under Contract DE-SC0012704, and by the Ernest Courant Traineeship in Accelerator Science and Technology Award No. DE-SC0020375. The Electron Ion Collider (EIC) is under design at Brookhaven National Laboratory. The EIC aims at providing high luminosity and high polarization collisions for a large range of beam energies. Dynamic aperture (DA) of the EIC Electron Storage Ring (ESR) must be sufficiently large in both transverse and momentum dimensions. The latter is a challenge due to low-beta optics in up to two interaction regions (IR). We have developed an advanced technique for efficient non-linear chromaticity compensation compatible with the different ESR lattice configurations at different energies. The solution for the most challenging lattice with two IRs at 18 GeV is presented. The lattice is then evaluated with magnet errors, where the error tolerances are determined for reaching the desired DA.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT043
About •	Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT047	Beam Optics of the Injection/Extraction and Beam Transfer in the Electron Rings of the EIC Project	injection, extraction, electron, kicker	1964
	N. Tsoupas, D. Holmes, C. Liu, C. Montag, V. Ptitsyn, V.H. Ranjbar, J. Skaritka, J.E. Tuozzolo, E. Wang, F.J. Willeke BNL, Upton, New York, USA B. Bhandari Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy. The Electron-Ion Collider (EIC) project* has been approved by the Department of Energy to be built at the site of Brookhaven National Laboratory (BNL). The goal of the project is the collision of energetic (of many GeV/amu) ion species with electron bunches of energies up to 18 GeV. The EIC includes two electron rings, the Rapid Cycling Synchrotron (RCS) which accelerates the electron beam up to 18 GeV, and the Electron Storage Ring (ESR) which stores the electron beam for collisions with hadron beam, both to be installed in the same tunnel as the Hadron Storage Ring (HSR). This paper discusses the layout and the beam optics of the injection/extraction beam lines the electron rings and the beam optics of the transfer line from the RCS to the ESR ring. * https://www.bnl.gov/eic/
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT047
About •	Received ※ 05 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT060	Controlling Landau Damping via Feed-Down From High-Order Correctors in the LHC and HL-LHC	target, simulation, MMI, controls	1995
	J. Dilly, E.H. Maclean, R. Tomás García CERN, Meyrin, Switzerland
	Funding: This work has been supported by the HiLumi Project and been sponsored by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Re-search. Amplitude detuning measurements in the LHC have shown that a significant amount of detuning is generated in Beam 1 via feed-down from decapole and dodecapole field errors in the triplets of the experiment insertion regions, while in Beam 2 this detuning is negligible. In this study, we investigate the cause of this behavior and we attempt to find corrections that use the feed-down from the nonlinear correctors in the insertion region for amplitude detuning.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT060
About •	Received ※ 07 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOPT061	A Flexible Nonlinear Resonance Driving Term Based Correction Algorithm with Feed-Down	luminosity, resonance, dipole, insertion	1999
	J. Dilly, R. Tomás García CERN, Meyrin, Switzerland
	Funding: This work has been supported by the HiLumi Project and been sponsored by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Re-search. The optics in the insertion regions of the LHC and its upgrade project the High Luminosity LHC are very sensitive to local magnetic errors, due to the extremely high beta-functions. In collision optics, the non-zero closed orbit in the same region leads to a "feed-down" of high-order errors to lower orders, causing additional effects detrimental to beam lifetime. An extension to the well-established method for correcting these errors by locally suppressing resonance driving terms has been undertaken, not only taking this feed-down into account, but also adding the possibility of utilizing it such that the powering of higher-order correctors will compensate for lower order errors. Existing correction schemes have also operated on the assumption of (anti-)symmetric beta-functions of the optics in the two rings. This assumption can fail for a multitude of reasons, such as inherently asymmetric optics and unevenly distributed errors. In this respect, an extension of this correction scheme has been developed, removing the need for symmetry by operating on the two separate optics of the beams simultaneously.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT061
About •	Received ※ 07 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK006	Proton Beamline Simulations for the High Intensity Muon Beamline at PSI	target, simulation, proton, cyclotron	2036
	M. Haj Tahar, D.C. Kiselev, A. Knecht, D. Laube, D. Reggiani, J. Snuverink, V. Talanov PSI, Villigen PSI, Switzerland
	The High Intensity Proton Accelerator (HIPA) cyclotron at the Paul Scherrer Institut (PSI) delivers 590 MeV CW proton beam with a maximum power of 1.42 MW. After extraction, the beam is transferred in a 120 m long channel towards two target stations (TgM and TgE) before depositing its remaining power at the spallation target SINQ for neutron production. As part of the High Intensity Muon Beamline (HIMB) feasibility study, which belongs to the IMPACT (Isotope and Muon Production using Advanced Cyclotron and Target technologies) initiative, the first of these targets will be replaced with a thicker one and its geometry opti- mized thereby specifically boosting the emission of surface muons. In order to assess the impact of the changes on the proton beamline, BDSIM/GEANT4 simulations were performed with the realistic technical design of the target insert, the collimation system was redesigned and the power depositions were benchmarked with MCNP6. In this paper, we discuss the major changes and challenges for HIMB as well as the key considerations in redesigning the optics of the high power beam in the vicinity of the target stations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK006
About •	Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 27 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK014	Hadron Storage Ring 4 O’clock Injection Design and Optics for the Electron-Ion Collider	injection, electron, septum, dipole	2068
	H. Lovelace III, J.S. Berg, D. Bruno, C. Cullen, K.A. Drees, W. Fischer, X. Gu, R.C. Gupta, D. Holmes, R.F. Lambiase, C. Liu, C. Montag, S. Peggs, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, M. Valette, D. Weiss BNL, Upton, New York, USA B. Bhandari, F. Micolon, N. Tsoupas, S. Verdú-Andrés Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA B.R. Gamage, T. Satogata, W. Wittmer JLab, Newport News, Virginia, USA
	The Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC) will accelerate protons and heavy ions up to a proton energy of 275 GeV and an Au⁺⁷⁹ 110 GeV/u to collide with electrons of energies up to 18 GeV. To accomplish the acceleration process, the hadrons are pre-accelerated in the Alternating Gradient Synchrotron (AGS), extracted, and transferred to HSR for injection. The planned area for injection is the current Relativistic Heavy Ion Collider (RHIC) 4 o’clock straight section. To inject hadrons, a series of modifications must be made to the existing RHIC 4 o’clock straight section to accommodate for the 20 new ~18 ns injection kickers and a new injection septum, while providing sufficient space and proper beam conditions for polarimetry equipment. These modifications will be discussed in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK014
About •	Received ※ 02 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOTK034	LHC Beam Collimation During Extended β*-Levelling in Run 3	collimation, luminosity, operation, experiment	2138
	F.F. Van der Veken, R. Bruce, M. Hostettler, D. Mirarchi, S. Redaelli CERN, Meyrin, Switzerland
	During the third operational Run of the Large Hadron Collider at CERN, starting in 2022, the bunch population will be increased to unprecedented levels requiring to deploy β^*-levelling of the luminosity over a wide range of values to cope with the limitations imposed by event pile-up at the experiments and heat load on the triplets induced by collision debris. During this levelling, both beam optics and orbit change in various areas of the ring, in particular around the high-luminosity experiments, where several collimators are installed. This requires adapting the collimation system settings adequately, in particular for the tertiary collimators (TCTs) that protect the inner-triplet magnets. To this end, two strategies are considered: keeping collimators at fixed physical openings while shifting their centres following the beam orbit, or varying also the collimator openings. The latter strategy is planned when the larger optics range will be deployed. In this paper, we investigate several loss scenarios at the TCTs in different steps of the levelling, and present the proposed collimator settings during Run 3.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK034
About •	Received ※ 07 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 07 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS031	Light Path Construction for an Optical Stochastic Cooling Stability Test at the Cornell Electron Storage Ring	radiation, experiment, synchrotron, feedback	2315
	S.J. Levenson, M.B. Andorf, I.V. Bazarov, D.C. Burke, J.M. Maxson, D.L. Rubin, S. Wang Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams and NYSTAR award C150153. An experiment at the Cornell Electron Storage Ring (CESR) to test the optical path-length stability of a bypass suitable for Optical Stochastic Cooling (OSC) is being pursued. The approximately 80 m light path for this experiment has been assembled, and synchrotron light has been successfully propagated from both sources. A feedback system based on an Electro-Optic Modulator (EOM) to correct the path-error accumulated in both the light and particle path has been table-top tested. We present on the design and construction of the light optics for the OSC stability experiment at CESR.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS031
About •	Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS035	Harpy: A Fast, Simple and Accurate Harmonic Analysis with Error Propagation	betatron, synchrotron, operation, coupling	2326
	L. Malina DESY, Hamburg, Germany
	Traditionally, in the accelerator physics field, accurate harmonic analysis has been performed by iteratively interpolating the result of Fast Fourier Transform (FFT) in the frequency domain. Such an approach becomes computationally demanding when relatively small effects are being studied, which is especially evident in the typical example of harmonic analysis of turn-by-turn beam position monitor data, i.e. many correlated but noisy signals. A new harmonic analysis algorithm, called Harpy, is about an order of magnitude faster than other methods, while often being also more accurate. Harpy combines standard techniques such as zero-padded FFT and noise-cleaning based on singular value decomposition. This combination also allows estimating errors of phases and amplitudes of beam-related harmonics calculated from cleaned data.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS035
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 20 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS043	UFO, a GPU Code Tailored Toward MBA Lattice Optimization	GPU, lattice, electron, simulation	2346
	M. Carlà, M. Canals ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
	The complexity of multi-bend achromatic optics is such that computational tools performance has become a dominant factor in the design process a last generation synchrotron light source. To relieve the problem a new code (UFO) tailored toward performance was developed to assist the design of the ALBA-II optics. Two main strategies contribute to the performance of UFO: the execution flow follows a data parallel paradigm, well suited for GPU execution; the use of a just-in-time compiler allows to simplify the computation whenever the lattice allows for it. At the core of UFO lies a parallel tracking routine structured for parallel simulation of optics which differs in some parameters, such as magnet strength or alignment, but retains the same element order, reflecting the scenario found in optimization processes, or when dealing with magnetic or alignment errors. Such an approach allows to take advantage of GPUs which yield the best performance when running thousands of parallel threads. Moreover UFO is not limited to tracking. A few modules that rely on the same tracking routine allow for the fast computation of dynamic and momentum aperture, closed orbit and linear optics.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS043
About •	Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 21 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS047	Automated Design and Optimization of the Final Cooling for a Muon Collider	emittance, simulation, collider, solenoid	2358
	E. Fol, D. Schulte, B. Stechauner CERN, Meyrin, Switzerland C.T. Rogers STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom J. Schieck HEPHY, Wien, Austria
	The desired beam emittance for a Muon collider is several orders of magnitude less than the one of the muon beams produced at the front-end target. Ionization cooling has been demonstrated as a suitable technique for the reduction of the muon beam emittance. Final cooling, as one of the most critical stages of the muon collider complex, necessitates careful design and optimization in order to control the beam dynamics and ensure efficient emittance reduction. We present an optimization framework based on ICool simulation code and application of different optimization algorithms, to automatize the choice of optimal initial muon beam parameters and simultaneous tuning of numerous final cooling components.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS047
About •	Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOMS052	Impacts of an ATS Lattice on EIC Dynamic Aperture	sextupole, lattice, electron, collider	2373
	J.E. Unger, J.A. Crittenden, G.H. Hoffstaetter Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA D. Marx BNL, Upton, New York, USA
	The Electron-Ion Collider (EIC) project at Brookhaven National Laboratory has explored strategies for increasing the energy aperture of the Electron Storage Ring (ESR) to meet the goal of 1\% for the 90 degree lattice at 18 GeV. Current strategies use a four sextupole family per arc correction scheme to increase the energy aperture and to keep the transverse aperture sufficiently large as well. A scheme called Achromatic Telescopic Squeezing (ATS), first introduced for the Large Hadron Collider, introduces a beta-beat into select arcs, allowing dynamic aperture optimizations with different sextupole strengths. The ATS scheme’s mix of some higher beta-function and some lower sextupole strengths in the arcs has the potential to increase the energy aperture. Basic chromatic corrections and numeric optimizations were used to compare the ATS optics to a non-ATS scheme. In all cases, the ATS scheme performed similarly or better than the more common schemes. However, this increase in energy aperture from the ATS optics also has negative effects, such as an increase in emittance which poses complications for the current ESR design.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS052
About •	Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT006	Beam Dynamics Observations at Negative Momentum Compaction Factors at KARA	sextupole, damping, synchrotron, operation	2570
	P. Schreiber, M. Brosi, B. Härer, A. Mochihashi, A.-S. Müller, A.I. Papash, R. Ruprecht, M. Schuh KIT, Karlsruhe, Germany
	Funding: We are supported by the DFG-funded "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology" and European Union’s Horizon 2020 research and innovation programme (No 730871) For the development of future synchrotron light sources new operation modes often have to be considered. One such mode is the operation with a negative momentum compaction factor to provide the possibility of increased dynamic aperture. For successful application in future light sources, the influence of this mode has to be investigated. At the KIT storage ring KARA (Karlsruhe Research Accelerator), operation with negative momentum compaction has been implemented and the dynamics can now be investigated. Using a variety of high-performance beam diagnostics devices it is possible to observe the beam dynamics under negative momentum compaction conditions. This contribution presents different aspects of the results of these investigations in the longitudinal and transversal plane.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT006
About •	Received ※ 08 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 08 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT013	Emittance Reduction with the Variable Dipole for the ELETTRA 2.0 Ring	dipole, emittance, lattice, damping	2586
	A. Poyet, Y. Papaphilippou CERN, Meyrin, Switzerland M.A. Domínguez, F. Toral CIEMAT, Madrid, Spain R. Geometrante, E. Karantzoulis Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy R. Geometrante KYMA, Trieste, Italy
	ELETTRA is a 2/2.4 GeV third-generation electron storage ring, located near Trieste, Italy. In view of a substantial increase of the machine performance in terms of brilliance, the so-called ELETTRA 2.0 upgrade is currently on-going. This upgrade is based on a 6-bends achromat, four dipoles of which having a longitudinally variable field. So far, those dipoles are foreseen to provide a field with a two step profile. The VAriable Dipole for the ELETTRA Ring (VADER) task, driven by the I.FAST European project, aims at developing a new dipole design based on a trapezoidal shape of the bending radius, which would allow for a further reduction of the horizontal emittance. A prototype of this magnet should be designed by the CIEMAT laboratory and built by KYMA company. This paper discusses the new dipole field specification and describes the corresponding optics optimization that was performed in order to reduce at best the emittance of the ELETTRA ring.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT013
About •	Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT016	Commissioning Simulations for the DIAMOND-II Upgrade	MMI, injection, storage-ring, quadrupole	2598
	H.C. Chao, R.T. Fielder, J. Kallestrup, I.P.S. Martin, B. Singh DLS, Oxfordshire, United Kingdom
	The Diamond-II storage ring, compared to Diamond, improves the natural beam emittance from 2.7 nm to 160 pm and the beam energy from 3 to 3.5 GeV. The number of straight sections is also doubled from 24 to 48 thanks to the modified hybrid six-bend-achromat lattice. To reduce the impact on the existing science program, the dark time period must be minimised. To assist in this aim, storage ring commissioning simulations have been carried out to predict and resolve possible issues. These studies include beam commissioning starting from on-axis first-turn beam threading up to beam based alignment and full linear optics correction with stored beam. The linear optics corrections with insertion devices are also included. The machine characterisations at different stages are compared. Considerations on realistic chamber limitations, error definitions and some commissioning strategies are also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT016
About •	Received ※ 19 May 2022 — Accepted ※ 15 June 2022 — Issue date ※ 15 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPT068	Linear Canonical Transform Library for Fast Coherent X-Ray Wavefront Propagation	radiation, synchrotron, operation, synchrotron-radiation	2759
	B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov RadiaSoft LLC, Boulder, Colorado, USA N.B. Goldring STATE33 Inc., Portland, Oregon, USA
	Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593. X-ray beamlines are essential components of all synchrotron light sources, transporting radiation from the stored electron beam passing from the source to the sample. The linear optics of the beamline can be captured via an ABCD matrix computed using a ray tracing code. Once the transport matrix is available, one may then include diffraction effects and arbitrary wavefront structure by using that same information in a Linear Canonical Transform (LCT) applied to the initial wavefront. We describe our implementation of a Python-based LCT library for 2D synchrotron radiation wavefronts. We have thus far implemented the separable case and are in the process of implementing algorithms for the non-separable case. Rectangular apertures are also included. We have tested our work against corresponding wavefront computations using The Synchrotron Radiation Workshop (SRW) code. LCT vs. SRW timing and benchmark comparisons are given for undulator and bending magnet beamlines. This algorithm is being included in the Sirepo implementation of the Shadow ray tracing code. Finally, we describe our plans for application to partially coherent radiation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT068
About •	Received ※ 15 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOTK063	Open Source Software to Simulate Ti:Sapphire Amplifiers	laser, simulation, photon, experiment	2925
	D.L. Bruhwiler, D.T. Abell, B. Nash RadiaSoft LLC, Boulder, Colorado, USA Q. Chen, C.G.R. Geddes, C. Tóth, J. van Tilborg LBNL, Berkeley, USA N.B. Goldring STATE33 Inc., Portland, Oregon, USA
	Funding: This work is supported by the US Department of Energy, Office of High Energy Physics under Award Numbers DE-SC0020931 and DE-AC02-05CH11231. The design of next-generation PW-scale fs laser systems, including scaling to kHz rates and development of new laser gain media for efficiency, will require parallel multiphysics simulations with realistic errors and nonlinear optimization. There is currently a lack of broadly available modeling software that self-consistently captures the required physics of gain, thermal loading and lensing, spectral shaping, and other effects required to quantitatively design such lasers.* We present initial work towards an integrated multiphysics capability for modeling pulse amplification in Ti:Sa lasers. All components of the software suite are open source. The Synchrotron Radiation Workshop (SRW)** is being used for physical optics, together with Python utilities. The simulations are being validated against experiments. * R. Falcone et al., Brightest Light Initiative Workshop Report (2019). ** https://github.com/ochubar/srw
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK063
About •	Received ※ 14 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS001	TURBO: A Novel Beam Delivery System Enabling Rapid Depth Scanning for Charged Particle Therapy	proton, dipole, controls, multipole	2929
	J.S.L. Yap, S.L. Sheehy The University of Melbourne, Melbourne, Victoria, Australia R.B. Appleby, H.X.Q. Norman, A.F. Steinberg UMAN, Manchester, United Kingdom
	Charged particle therapy (CPT) is a well-established modality of cancer treatment and is increasing in worldwide presence due to improved accelerator technology and modern techniques. The beam delivery system (BDS) determines the overall timing and beam shaping capabilities, but is restricted by the energy variation speed: energy layer switching time (ELST). Existing treatment beamlines have a ±1% momentum acceptance range, needing time to change the magnetic fields as the beam is delivered in layers at various depths across the tumour volume. Minimising the ELST can enable the delivery of faster, more effective and advanced treatments but requires an improved BDS. A possibility for this could be achieved with a design using Fixed Field Alternating Gradient (FFA) optics, enabling a large energy acceptance to rapidly transport beams of varying energies. A scaled-down, novel system - Technology for Ultra Rapid Beam Operation (TURBO) - is being developed at the University of Melbourne, to explore the potential of rapid depth scanning. Initial simulation studies, beam and field measurements, project plans and clinical considerations are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS001
About •	Received ※ 20 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS002	Gantry Beamline and Rotator Commissioning at the Medaustron Ion Therapy Center	MMI, proton, quadrupole, radiation	2933
	M.T.F. Pivi, L. Adler, G. Guidoboni, G. Kowarik, C. Kurfürst, C. Maderböck, D.A. Prokopovich, I. Strašík EBG MedAustron, Wr. Neustadt, Austria G. Kowarik GKMT Consulting, Consulting and Project Management, Vienna, Austria M. Pavlovič STU, Bratislava, Slovak Republic M.G. Pullia CNAO Foundation, Pavia, Italy V. Rizzoglio PSI, Villigen PSI, Switzerland
	The MedAustron Particle Therapy Accelerator located in Austria, delivers proton beams in the energy range 60-250 MeV/n and carbon ions 120-400 MeV/n for medical treatment in two irradiation rooms, clinically used for tumor therapy. Proton beams up to 800 MeV/n are also provided to a room dedicated to scientific research. Over the last two years, in parallel to clinical operations, we have completed the installation and commissioning of the gantry beam line in a dedicated room, ready for the first patient treatment in early 2022. In this manuscript, we provide an overview of the MedAustron gantry beam commissioning including the world-wide first ’rotator’ system, a rotating beamline located upstream of the gantry and used to match the slowly extracted non-symmetric beams into the coordinate system of the gantry. Using the rotator, all beam parameters at the location of the patient become independent of the gantry rotation angle. Furthermore, both the gantry and the high energy transfer line optics had to be redesigned and adapted to the rotator-mode of operation. A review of the beam commissioning including technical solutions, main results and reference measurements is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS002
About •	Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 04 July 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS011	Beam Optics Studies for a Novel Gantry for Hadrontherapy	dipole, quadrupole, operation, hadrontherapy	2962
	E. Felcini, G. Frisella, A. Mereghetti, M.G. Pullia, S. Savazzi CNAO Foundation, Pavia, Italy E. Benedetto SEEIIST, Geneva, Switzerland M.T.F. Pivi EBG MedAustron, Wr. Neustadt, Austria
	Funding: This study was (partially) supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101008548 (HITRIplus). The design of smaller and less costly gantries for carbon ion particle therapy represents a major challenge to the diffusion of this treatment. Here we present the work done on the linear beam optics of possible gantry layouts, differing for geometry, momentum acceptance, and magnet technology, which share the use of combined function superconducting magnets with a bending field of 4T. We performed parallel-to-point and point-to-point optics matching at different magnification factors to provide two different beam sizes at the isocenter. Moreover, we considered the orbit distortion generated by magnet errors and we introduced beam position monitors and correctors. The study, together with considerations on the criteria for comparison, is the basis for the design of a novel and compact gantry for hadrontherapy.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS011
About •	Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 30 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS012	Explorative Studies of an Innovative Superconducting Gantry	dipole, superconducting-magnet, quadrupole, hadrontherapy	2966
	M.G. Pullia, M. Donetti, E. Felcini, G. Frisella, A. Mereghetti, A. Mirandola, A. Pella, S. Savazzi CNAO Foundation, Pavia, Italy E. Benedetto SEEIIST, Geneva, Switzerland L. Dassa, M. Karppinen, D. Perini, D. Tommasini, M. Vretenar CERN, Meyrin, Switzerland E. De Matteis, L. Rossi INFN/LASA, Segrate (MI), Italy C. Kurfürst, M.T.F. Pivi, M. Stock EBG MedAustron, Wr. Neustadt, Austria S. Mariotto, M. Prioli INFN-Milano, Milano, Italy L. Piacentini, A. Ratkus, T. Torims, J. Vilcans Riga Technical University, Riga, Latvia L. Sabbatini, A. Vannozzi LNF-INFN, Frascati, Italy S. Uberti Università di Brescia, Brescia, Italy
	Funding: This study was (partially) supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101008548 (HITRIplus). The Heavy Ion Therapy Research Integration plus (HITRIplus) is a European project that aims to integrate and propel research and technologies related to cancer treatment with heavy ions beams. Among the ambitious goals of the project, a specific work package includes the design of a gantry for carbon ions, based on superconducting magnets. The first milestone to achieve is the choice of the fundamental gantry parameters, namely the beam optics layout, the superconducting magnet technology, and the main user requirements. Starting from a reference 3T design, the collaboration widely explored dozens of possible gantry configurations at 4T, aiming to find the best compromise in terms of footprint, capital cost, and required R&D. We present here a summary of these configurations, underlying the initial correlation between the beam optics, the mechanics, and the main superconducting dipoles design: the bending field (up to 4 T), combined function features (integrated quadrupole), magnet aperture (up to 90 mm), and angular length (30°-45°). The resulting main parameters are then listed, compared, and used to drive the choice of the best gantry layout to be developed in HITRIplus.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS012
About •	Received ※ 20 May 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)

THPOMS018	Study of Coil Configuration and Local Optics Effects for the GaToroid Ion Gantry Design	focusing, hadrontherapy, hadron, radiation	2984
	E. Oponowicz, L. Bottura, Y. Dutheil, A. Gerbershagen, A. Haziot CERN, Meyrin, Switzerland
	Funding: Project co-funded by the CERN Budget for Knowledge Transfer to Medical Applications. GaToroid, a novel configuration for hadron therapy gantry, is based on superconducting coils that gen- erate a toroidal magnetic field to deliver the beam onto the patient. Designing the complex GaToroid coils requires careful consideration of the local beam optical effects. We present a Python-based tool for charged particle transport in complex electromagnetic fields. The code implements fast tracking in arbitrary three-dimensional field maps, and it is not limited to specific or regular reference trajectories, as is generally the case in accelerator physics. The tool was used to characterise the beam behaviour inside the GaToroid system. It automatically determines the reference trajectories in the symmetry plane and analyses three-dimensional beam dynamics around these trajectories. Beam optical parameters in the field region were compared for various magnetic configurations of GaToroid. This paper introduces the new tracker and shows the benchmarking results. Furthermore, first- order beam optics studies for different arrangements demonstrate the main code features and serve for the design optimisation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS018
About •	Received ※ 19 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 23 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS020	Beam Optics Study for a Potential VHEE Beam Delivery System	scattering, electron, quadrupole, dipole	2992
	C.S. Robertson, P. Burrows JAI, Oxford, United Kingdom M. Dosanjh, A. Gerbershagen, A. Latina CERN, Meyrin, Switzerland
	VHEE (Very High Energy Electron) therapy can be superior to conventional radiotherapy for the treatment of deep seated tumours, whilst not necessarily requiring the space and cost of proton or heavy ion facilities. Developments in high gradient RF technology have allowed electrons to be accelerated to VHEE energies in a compact space, meaning that treatment could be possible with a shorter linac. A crucial component of VHEE treatment is the transfer of the beam from accelerator to patient. This is required to magnify the beam to cover the transverse extent of the tumour, whilst ensuring a uniform beam distribution. Two principle methodologies for the design of a compact transfer line are presented. The first of these is based upon a quadrupole lattice and optical magnification of beam size. A minimisation algorithm is used to enforce certain criteria on the beam distribution at the patient, defining the lattice through an automated routine. Separately, a dual scattering-foil based system is also presented, which uses similar algorithms for the optimisation of the foil geometry in order to achieve the desired beam shape at the patient location.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS020
About •	Received ※ 19 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS024	A Novel Intensity Compensation Method to Achieve Energy Independent Beam Intensity at the Patient Location for Cyclotron Based Proton Therapy Facilities	cyclotron, proton, emittance, beam-losses	3004
	V. Maradia, A.L. Lomax, D. Meer, S. Psoroulas, D.C. Weber PSI, Villigen PSI, Switzerland V. Maradia ETH, Zurich, Switzerland
	Funding: This work is supported by a PSI inter-departmental funding initiative (Cross) In cyclotron-based proton therapy facilities, an energy selection system is typically used to lower beam energy from the fixed value provided by the accelerator (250/230MeV) to the one needed for the treatment (230-70MeV). Such a system has drawback of introducing an energy-dependent beam current at the patient location, resulting in energy-dependent beam intensity ratios of about 10³ between high and low energies. This complicates treatment delivery and challenges patient safety systems. As such, we propose the use of a dual-energy degrader method that can reduce beam intensity for high-energy beams. The first degrader is made of high Z material and the second is made of low Z material and are placed next to each other. For high energies (230-180MeV), we use only first degrader to increase beam emittance after degrader and thus lose intensity in emittance selection collimators. For intermediate energy beams (180-100MeV) we use the combination of both degraders, whereas for low energy beams (100-70MeV), only the second degrader limits the increase in emittance. With this approach, energy-independent beam intensities can be achieved, whilst localizing beam losses around the degrader.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS024
About •	Received ※ 16 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 14 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOMS025	A Novel Method of Emittance Matching to Increase Beam Transmission for Cyclotron Based Proton Therapy Facilities: Simulation Study	scattering, emittance, proton, cyclotron	3007
	V. Maradia, A.L. Lomax, D. Meer, S. Psoroulas, J.M. Schippers, D.C. Weber PSI, Villigen PSI, Switzerland V. Maradia ETH, Zurich, Switzerland
	Funding: This work is supported by a PSI inter-departmental funding initiative (Cross) In proton therapy, high dose rates can reduce treatment delivery times, allowing for efficient mitigation of tumor motion and increased patient throughput. With cyclotrons, however, high dose rates are difficult to achieve for low-energies as, typically, the emittance after the degrader is matched in both transversal planes using circular collimators, which does not provide an optimal matching to the acceptance of the following beamline. Transmission can however be substantially improved by transporting maximum acceptable emittances in both orthogonal planes, but at the cost of gantry angle-dependent beam shapes at isocenter. Here we demonstrate that equal emittances in both planes can be recovered at the gantry entrance using a thin scattering foil, thus ensuring gantry angle-independent beam shapes at the isocenter. We demonstrate experimentally that low-energy beam transmission can be increased by a factor of 3 using this approach compared to the currently used beam optics, whilst gantry angle-independent beam shapes are preserved. We expect that this universal approach could also bring a similar transmission improvement in other cyclotron-based proton therapy facilities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS025
About •	Received ※ 16 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 28 June 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPOST024

A Local Modification of HL-LHC Optics for Improved Performance of the Alice Fixed-Target Layout

target, proton, collimation, experiment

108

M. Patecki, D. Kikoła
Warsaw University of Technology, Warsaw, Poland
A.S. Fomin, P.D. Hermes, D. Mirarchi, S. Redaelli
CERN, Meyrin, Switzerland

Funding: This project has received funding from the European Union’s Horizon 2020 research and innovation programme, grant agreement number 101003442 - FIXEDTARGETLAND.
The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) is the world’s largest and most powerful particle accelerator colliding beams of protons and lead ions at energies up to 7 TeV and 2.76 TeV, respectively. ALICE is one of the detector experiments optimised for heavy-ion collisions. A fixed-target experiment in ALICE is considered to collide a portion of the beam halo, split using a bent crystal, with an internal target placed a few meters upstream of the detector. Fixed-target collisions offer many physics opportunities related to hadronic matter and the quark-gluon plasma to extend the research potential of the CERN accelerator complex. Production of physics events depends on the particle flux on target. The machine layout for the fixed-target experiment is being developed to provide a flux of particles on a target high enough to exploit the full capabilities of the ALICE detector acquisition system. In this paper, we discuss a method of increasing the system’s performance by applying a local modification of optics to set the crystal at the optimal betatron phase.
marcin.patecki@pw.edu.pl

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST024

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022

Cite •

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

MOPOST039

Algorithm to Mitigate Magnetic Hysteresis in Magnets with Unipolar Power Supplies

quadrupole, power-supply, ISAC, cyclotron

156

J. Nasser, R.A. Baartman, O.K. Kester, S. Kiy, T. Planche, S.D. Rädel, O. Shelbaya
TRIUMF, Vancouver, Canada

Funding: National Research Council Canada
The effects of hysteresis on the fields produced by magnetic lenses are not accounted for in TRIUMF’s models of the accelerators. Under certain conditions, such as quadrupoles with unipolar power supplies operating at low currents, these effects have introduced significant field errors with consequences upon tranverse tunes. To combat these uncertainties and make the fields more reproducible and stable, a technique new to TRIUMF has been implemented. This technique ramps the current cyclically about the desired setpoint to reach a reproducible field that is independent of its history. Results of magnetic measurements at TRIUMF using this technique are presented, as well as the expected improvements to the accuracy of the beam optics model, particularly for unipolar quadrupoles.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST039

About •

Received ※ 03 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022

Cite •

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

MOPOST041

Dynamic Aperture Studies for the Transfer Line From FLUTE to cSTART

storage-ring, quadrupole, simulation, linac

164

J. Schäfer, B. Härer, A.-S. Müller, A.I. Papash, R. Ruprecht, M. Schuh
KIT, Karlsruhe, Germany

Funding: J. Schäfer acknowledges the support by the DFG- funded Doctoral School "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology".
The compact STorage ring for Accelerator Research and Technology cSTART project will deliver a new KIT accelerator test facility for the application of novel acceleration techniques and diagnostics. The goal is to demonstrate storing an electron beam of a Laser Plasma Accelerator (LPA) in a compact circular accelerator for the first time. Before installing an LPA, the Far-Infrared Linac and Test Experiment (FLUTE) will serve as a full energy injector for the compact storage ring, providing stable bunches with a length down to a few femtoseconds. The transport of the bunches from FLUTE to the cSTART storage ring requires a transfer line which includes horizontal, vertical and coupled deflections which leads to coupling of the dynamics in the two transverse planes. In order to realize ultra-short bunch lengths at the end of the transport line, it relies on special optics which invokes high and negative dispersion. This contribution presents dynamic aperture studies based on six-dimensional tracking through the lattice of the transfer line.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOST041

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 24 June 2022

Cite •

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

MOPOPT020

Longitudinal Phase Space Diagnostics with Corrugated Structure at the European XFEL

electron, diagnostics, FEL, laser

275

S. Tomin, W. Decking, N. Golubeva, A.I. Novokshonov, T. Wohlenberg, I. Zagorodnov
DESY, Hamburg, Germany

Characterization of the longitudinal phase space (LPS) of the electron beam after the FEL process is important for its study and tuning. At the European XFEL, a single plate corrugated structure was installed after the SASE2 undulator to measure the LPS of the electron beam. The beam passing near the plate’s corrugations creates wakefields, which induce a correlation between time and the transverse distribution of the beam. The longitudinal phase space of the beam is then analyzed on a scintillating screen monitor placed in the dispersion section. In this paper, we present the result of commissioning the corrugated structure and the first LPS measurement.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT020

About •

Received ※ 12 June 2022 — Revised ※ 12 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 21 June 2022

Cite •

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

MOPOPT031

Renovation of the SR Beam Profile Monitors with Novel Polycrystalline Diamond Mirrors at the SuperKEKB Accelerator

extraction, laser, radiation, synchrotron

313

G. Mitsuka, H. Ikeda, T.M. Mitsuhashi
KEK, Ibaraki, Japan

SR beam profile monitors are fundamental to perform the stable beam operation of SuperKEKB. To suppress thermal deformation of SR extraction mirrors–a long-standing issue in SR monitors–, we developed platinum coated diamond mirrors in 2019. The diamond mirrors are made with optical-quality polycrystal-diamond-substrate with extremely large thermal conductivity, and have a size of 20 mm (W) x 30 mm (H) x 2 mm (D). Surface flatness better than λ/5 was observed in an optical testing with a laser interferometer. The diamond mirrors have been installed in HER and LER in 2020 summer and 2021 summer, respectively. Through irradiation for an year at the beam current greater than 800 mA, no significant deformation of the diamond mirrors has been observed. In this talk, we will discuss the design, construction, and optical testing of the polycrystal diamond mirrors. Also beam measurements performed using an interferometer, a coronagraph, a streak camera, and a fast gate camera will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT031

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 02 July 2022

Cite •

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

MOPOPT047

Experimental Demonstration of Machine Learning Application in LHC Optics Commissioning

quadrupole, MMI, simulation, diagnostics

359

E. Fol, F.S. Carlier, J. Dilly, M. Hofer, J. Keintzel, M. Le Garrec, E.H. Maclean, T.H.B. Persson, F. Soubelet, R. Tomás García, A. Wegscheider
CERN, Meyrin, Switzerland
J.F. Cardona
UNAL, Bogota D.C, Colombia

Recently, we conducted successful studies on the suitability of machine learning (ML) methods for optics measurements and corrections, incorporating novel ML-based methods for local optics corrections and reconstruction of optics functions. After performing extensive verifications on simulations and past measurement data, the newly developed techniques became operational in the LHC commissioning 2022. We present the experimental results obtained with the ML-based methods and discuss future improvements. Besides, we also report on improving the Beam Position Monitor (BPM) diagnostics with the help of the anomaly detection technique capable to identify malfunctioning BPMs along with their possible fault causes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOPT047

About •

Received ※ 07 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 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, vacuum, experiment, 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)

MOPOTK002

Fast Orbit Response Matrix Measurement via Sine-Wave Excitation of Correctors at Sirius

storage-ring, synchrotron, quadrupole, lattice

425

M.M.S. Velloso, M.B. Alves, F.H. de Sá
LNLS, Campinas, Brazil

Sirius is the new 4th generation storage ring based synchrotron light source built and operated by the Brazilian Synchrotron Light Laboratory (LNLS). In this work, we report on the implementation at Sirius of a fast method for orbit response matrix (ORM) measurement which is based on sine-wave parallel excitation of orbit corrector magnets’ strength. This ‘‘AC method" has reduced the ORM measurement time from ∼ 25 minutes to 2.5-3 minutes and displayed increased precision if compared to the standard serial measurement procedure. When used as input to the Linear Optics from Closed Orbits (LOCO) correction algorithm, the AC ORM yielded similar optics corrections with less aggressive quadrupoles strength changes.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK002

About •

Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 22 June 2022

Cite •

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

MOPOTK004

Status of the Soleil Upgrade Lattice Robustness Studies

lattice, injection, MMI, simulation

433

O.R. Blanco-García
INFN/LNF, Frascati, Italy
D. Amorim, A. Loulergue, L.S. Nadolski, R. Nagaoka
SOLEIL, Gif-sur-Yvette, France
M.A. Deniaud
JAI, Egham, Surrey, United Kingdom

The SOLEIL synchrotron has entered its Technical Design Report (TDR) phase for the upgrade of its storage ring to a fourth generation synchrotron light source. Verification of the equipment specifications (alignment, magnets, power supplies, BPMs), and the methodology for optics corrections are critical in order to ensure the feasibility of rapid commissioning restoring full performance for daily operations. The end-to-end simulation, from beam threading in the first turns to beam storage and stacking, should be handled with a comprehensive model close to the actual commissioning procedure, taking into account all practical steps. During 2021 and 2022, the CDR lattice has undergone significant modifications in response to additional constraints. In this paper, we present an update of the robustness studies for the TDR baseline lattice.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK004

About •

Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022

Cite •

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

MOPOTK006

Off-Energy Operation for the ESRF-EBS Storage Ring

SRF, injection, sextupole, lattice

437

L. Hoummi, T. Brochard, N. Carmignani, L.R. Carver, J. Chavanne, S.M. Liuzzo, T.P. Perron, R. Versteegen, S.M. White
ESRF, Grenoble, France
P. Raimondi
SLAC, Menlo Park, California, USA

The ESRF-EBS is the first 4th generation source making use of the Hybrid Multi-Bend Achromat (HMBA) lattice cell, reaching an equilibrium horizontal emittance of 140 pm.rad in user mode (insertion devices (ID) gaps open). The injection in the storage ring (SR) is conducted with a short booster, operated off-energy. The RF frequency is increased compared to the nominal one to put the beam on a dispersive orbit, thus going off-axis in quadrupoles. The induced dipolar feed down effects reduce the booster horizontal emittance. The same strategy is extended to the ESRF-EBS SR, for an expected emittance reduction of about 20 pm.rad. A first approach shifts the RF frequency by +300 Hz to operate at -1% energy offset. Optimal quadrupole and sextupole settings are defined for this off-energy operation based on simulations. The settings are then tested in the SR in terms of dynamic aperture and injection efficiency.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK006

About •

Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 05 July 2022

Cite •

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

MOPOTK013

Machine Learning Based Surrogate Model Construction for Optics Matching at the European XFEL

simulation, quadrupole, electron, FEL

461

Z.H. Zhu, Y. Chen, W. Qin, M. Scholz, S. Tomin
DESY, Hamburg, Germany

Beam optics matching is a daily routine in the operation of an X-ray free-electron laser facility. Usually, linear optics is employed to conduct the beam matching in the control room. However, the collective effects like space charge dominate the electron bunch in the low-energy region which decreases the accuracy of the existing tool. Therefore, we proposed a scheme to construct a surrogate model with nonlinear optics and collective effects to speed up the optics matching in the European XFEL injector section. This model also facilitates further research on beam dynamics for the space-charge dominated beam.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK013

About •

Received ※ 07 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 28 June 2022

Cite •

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

MOPOTK014

Optics of a Recirculating Beamline for MESA

experiment, target, injection, scattering

465

C.P. Stoll, A. Meseck
KPH, Mainz, Germany

The Mainz Energy-recovering Superconducting Accelerator (MESA) is an Energy Recovery Linac (ERL) facility under construction at the Johannes Gutenberg-University in Mainz. It provides the opportunity for precision physics experiments with a 1 mA c.w. electron beam in its initial phase. In this phase experiments with unpolarised, high-density 10¹⁹ atoms per cm² gas jet targets are foreseen at the Mainz Gas Internal Target Experiment (MAGIX). To allow experiments with thin polarised gas targets with sufficiently high interaction rates in a later phase, the beam current must be increased to up to 100 mA, which would pose significant challenges to the existing ERL machine. Thus, it is proposed here to use MESA in pulsed operation with a repetition rate of several kHz to fill a recirculating beamline, providing a quasi c.w. beam current to a thin gas target. The optics necessary for this recirculating beamline are presented here.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK014

About •

Received ※ 01 June 2022 — Revised ※ 10 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 07 July 2022

Cite •

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

MOPOTK028

Zero Dispersion Optics to Improve Horizontal Emittance Measurements at the CERN Proton Synchrotron

emittance, quadrupole, simulation, space-charge

503

W. Van Goethem, F. Antoniou, F. Asvesta, H. Bartosik, A. Huschauer
CERN, Meyrin, Switzerland

In modern particle accelerators, the horizontal dispersion function is forced to zero at locations with instrumentation measuring the transverse beam distribution, in order to remove the dispersive contribution to the horizontal beam size. The design of the CERN Proton Synchrotron did not foresee such a zero-dispersion insertion, making it challenging to get a good precision on the beam size measurements. In this contribution, we present a new optics configuration, which allows to reach zero horizontal dispersion at the locations of different beam size measurement locations. This can be achieved by powering a set of trim quadrupoles, the so-called Low Energy Quadrupoles (LEQ). We investigate how the resulting optics perturbation affects beam parameters.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK028

About •

Received ※ 07 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 08 July 2022

Cite •

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

MOPOTK029

Improved Low-Energy Optics Control for Transverse Emittance Preservation at the CERN Proton Synchrotron

emittance, space-charge, quadrupole, lattice

507

W. Van Goethem, F. Antoniou, F. Asvesta, H. Bartosik, A. Huschauer
CERN, Meyrin, Switzerland

Preservation of the transverse emittances across the CERN accelerator chain is an important requirement for beams produced for the Large Hadron Collider (LHC). In the CERN Proton Synchrotron (PS), high brightness LHC-type beams are stored on a long flat bottom for up to 1.2 seconds. During this storage time, direct space charge effects may lead to resonance crossing and subsequent growth of the transverse emittances. Previous studies showed an important emittance increase when the PS working point is moved near integer tune values. Subsequent simulation studies confirmed that this observation is caused by an interplay of space charge effects and the optics beatings induced by the Low Energy Quadrupoles (LEQ). A new optics configuration using these quadrupoles to reduce the optics beating and the emittance growth was developed and experimentally validated. The results of simulation and experimental studies are presented in this contribution.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK029

About •

Received ※ 07 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 25 June 2022 — Issue date ※ 10 July 2022

Cite •

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

MOPOTK032

An N-BPM Momentum Reconstruction for Linear Transverse Coupling Measurements in LHC and HL-LHC

coupling, lattice, resonance, controls

519

A. Wegscheider, R. Tomás García
CERN, Meyrin, Switzerland

The measurement and control of linear transverse coupling is important for the operation of an accelerator. The calculation of the linear transverse coupling resonance driving terms (RDTs) ’1001 and ’1010 relies on the complex spectrum of the turn-by-turn motion. To obtain the complex signal, a reconstruction of the particle motion is needed. For this purpose, the signal of a second BPM with a suitable phase shift is usually used. In this work, we explore the possibility of including more BPMs in the reconstruction of the transverse momentum, which could reduce the effects of statistical errors and systematic uncertainties. This, in turn, could improve the precision and accuracy of the RDTs, which could be of great benefit for locations where an exact knowledge of the transverse coupling or other RDTs is important. We present the development of a new method to reconstruct the particle’s momentum that uses a statistical analysis of several nearby BPMs. The improved precision is demonstrated via simulations of LHC and HL-LHC lattices.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK032

About •

Received ※ 08 June 2022 — Revised ※ 23 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 27 June 2022

Cite •

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

MOPOTK036

Studies of the Vertical Excursion Fixed Field Alternating Gradient Accelerator

lattice, closed-orbit, quadrupole, simulation

535

M.E. Topp-Mugglestone, S.L. Sheehy
JAI, Oxford, United Kingdom
J.-B. Lagrange, S. Machida
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The Vertical Excursion Fixed Field Alternating Gradient Accelerator (VFFA) concept offers a number of advantages over existing accelerator archetypes, as discussed in previous works. However, the VFFA has nonplanar orbits by design and unavoidable transverse coupling. Hence, current understanding of the dynamics of this machine is limited; this paper presents some in-depth study of its behaviour using a combination of analytical and numerical techniques.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK036

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 20 June 2022

Cite •

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

MOPOTK037

Impact of Insertion Devices on Diamond-II Lattice

insertion, insertion-device, emittance, lattice

539

B. Singh, R.T. Fielder, H. Ghasem, J. Kallestrup, I.P.S. Martin, T. Olsson
DLS, Oxfordshire, United Kingdom

Funding: DLS ltd
The DIAMOND-II lattice is based on the ESRF-EBS cell, with the centre dipole replaced by a (chromatic) mid-straight, and a -I transformer, higher order achromat (HOA) & dispersion bumps to control the nonlinear dynamics. The majority of insertion devices currently on operation in Diamond will be either retained or upgraded as part of the Diamond-II program, and the new mid straights allow the total number of ID beamlines to be increased from 28 to 36.Therefore, it is important to investigate how IDs will affect the emittance, energy spread and linear and nonlinear beam dynamics. The kickmap approach has been used to model all IDs, including APPLE-II and APPLE-II Knot with active shim wires. In this paper, the outcome of these investigations will be presented and discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK037

About •

Received ※ 04 June 2022 — Accepted ※ 30 June 2022 — Issue date ※ 07 July 2022

Cite •

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

MOPOTK038

BPM Analysis with Variational Autoencoders

network, focusing, diagnostics, GPU

543

C.C. Hall, J.P. Edelen, J.A. Einstein-Curtis, M.C. Kilpatrick
RadiaSoft LLC, Boulder, Colorado, USA

Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of High Energy Physics under Award Number DE-SC0021699.
In particle accelerators, beam position monitors (BPMs) are used extensively as a non-intercepting diagnostic. Significant information about beam dynamics can often be extracted from BPM measurements and used to actively tune the accelerator. However, common measurement tools, such as measurements of kicked beams, may become more difficult when very strong nonlinearities are present or when data is very noisy. In this work, we examine the use of variational autoencoders (VAEs) as a technique to extract measurements of the beam from simulated turn-by-turn BPM data. In particular, we show that VAEs may have the possibility to outperform other dimensionality reduction techniques that have historically been used to analyze such data. When the data collection period is limited, or the data is noisy, VAEs may offer significant advantages.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK038

About •

Received ※ 09 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 10 July 2022

Cite •

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

MOPOTK046

Design Concept for a Second Interaction Region for the Electron-Ion Collider

electron, hadron, collider, detector

564

B.R. Gamage, V. Burkert, R. Ent, Y. Furletova, D.W. Higinbotham, T.J. Michalski, R. Rajput-Ghoshal, D. Romanov, T. Satogata, A. Seryi, C. Weiss, W. Wittmer, Y. Zhang
JLab, Newport News, Virginia, USA
E.C. Aschenauer, J.S. Berg, K.A. Drees, A. Jentsch, A. Kiselev, C. Montag, R.B. Palmer, B. Parker, V. Ptitsyn, F.J. Willeke, H. Witte
BNL, Upton, New York, USA
C. Hyde
ODU, Norfolk, Virginia, USA
F. Lin, V.S. Morozov
ORNL RAD, Oak Ridge, Tennessee, USA
P. Nadel-Turonski
SBU, Stony Brook, New York, USA

Funding: Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177, Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 and UT-Battelle, LLC, under contract No. DE-AC05-00OR22725
In addition to the day-one primary Interaction Region (IR), the design of the Electron Ion Collider (EIC) must support operation of a 2nd IR potentially added later. The 2nd IR is envisioned in an existing experimental hall at RHIC IP8, compatible with the same beam energy combinations as the 1st IR over the full center of mass energy range of ~20 GeV to ~140 GeV. The 2nd IR is designed to be complementary to the 1st IR. In particular, a secondary focus is added in the forward ion direction of the 2nd IR hadron beamline to optimize its capability in detecting particles with magnetic rigidities close to those of the ion beam. We provide the current design status of the 2nd IR in terms of parameters, magnet layout and beam dynamics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK046

About •

Received ※ 08 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 12 June 2022 — Issue date ※ 17 June 2022

Cite •

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

MOPOTK050

Linac Optics Optimization with Multi-Objective Optimization

linac, lattice, quadrupole, controls

572

I. Neththikumara, T. Satogata
ODU, Norfolk, Virginia, USA
R.M. Bodenstein, S.A. Bogacz, T. Satogata
JLab, Newport News, Virginia, USA
A. Vandenhoeke
ULB, Bruxelles, Belgium

Funding: This material is based upon work supported by the U.S. Department of Energy under contract DE-AC05-06OR23177.
The beamline design of recirculating linacs requires special attention to avoid beam instabilities due to RF wakefields. A proposed high-energy, multi-pass energy recovery demonstration at CEBAF uses a low beam current. Stronger focusing at lower energies is necessary to avoid beam breakup(BBU) instabilities, even with this small beam current. The CEBAF linac optics optimization balances over-focusing at higher energies and beta excursions at lower energies. Using proper mathematical expressions, linac optics optimization can be achieved with evolutionary algorithms. Here, we present the optimization process of North Linac optics using multi-objective optimization.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK050

About •

Received ※ 31 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 10 July 2022

Cite •

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

MOPOTK053

RLAs with FFA Arcs for Protons and Electrons

cavity, linac, SRF, hadron

584

V.S. Morozov
ORNL RAD, Oak Ridge, Tennessee, USA
J.F. Benesch, R.M. Bodenstein, S.A. Bogacz, A. Coxe, K.E. Deitrick, D. Douglas, B.R. Gamage, G.A. Krafft, K.E.Price. Price, Y. Roblin, A. Seryi
JLab, Newport News, Virginia, USA
J.S. Berg, S.J. Brooks, F. Méot, D. Trbojevic
BNL, Upton, New York, USA
D. Douglas
Douglas Consulting, York, Virginia, USA
G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Authored in part by UT-Battelle, LLC, Jefferson Science Associates, LLC, and Brookhaven Science Associates, LLC under Contracts DE-AC05-00OR22725, DE-AC05-06OR23177, and DE-SC0012704 with the US DOE.
Recirculating Linear Accelerators (RLAs) provide an efficient way of producing high-power, high-quality, continuous-wave hadron and lepton beams. However, their attractiveness had been limited by the cumbersomeness of multiple recirculating arcs and by the complexity of the spreader and recombiner regions. The latter problem sets one of the practical limitations on the maximum number of recirculations. We present an RLA design concept where the problem of multiple arcs is solved using the Fixed-Field Alternating gradient (FFA) design as in CBETA. The spreader/recombiner design is greatly simplified using an adiabatic matching approach. It allows for the spreader/recombiner function to be accomplished by a single beam line. The concept is applied to the designs of a high-power hadron accelerator being considered at ORNL and a CEBAF electron energy doubling project, FFA@CEBAF, being developed at Jefferson lab.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-MOPOTK053

About •

Received ※ 10 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)

TUOZSP1

Prospects for Optics Measuements in FCC-ee

damping, dipole, collider, radiation

827

J. Keintzel, R. Tomás García, F. Zimmermann
CERN, Meyrin, Switzerland

Within the framework of the Future Circular Collider Feasibility Study, the design of the electron-positron collider FCC-ee is optimised, as a possible future double collider ring, currently foreseen to start operation during the 2040s. With close to 100 km of circumference and strong synchrotron radiation damping at highest beam energy, adequate beam measurements are needed to control the optics at the desired level. Various possible techniques to measure the optics in FCC-ee are explored, including the option of turn-by-turn measurements in combination with an AC-dipole.

Slides TUOZSP1 [2.738 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUOZSP1

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 28 June 2022

Cite •

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

TUPOMS006

FILO: A New Application to Correct Optics in the ESRF-EBS Storage Ring

SRF, quadrupole, lattice, operation

1401

S.M. Liuzzo, N. Carmignani, L.R. Carver, L. Farvacque, L. Hoummi, T.P. Perron, B. Roche, B. Vedder, S.M. White
ESRF, Grenoble, France

A new optics correction application (Fit and Improvement of Linear Optics, FILO) was designed and set in place for the ESRF-EBS storage ring. The widely used software LOCO* is not available at ESRF and despite a few trials to set it in operation, it has been decided to write a new code. The application is flexible, may be used via the control system simulators and is adapted to a user friendly operation thanks to a wizard mode. Some features of LOCO are copied over, some others are yet to be implemented. The measurement of on and off-energy response matrices using slow or fast steerers is integrated in the same application. Results obtained with this application are presented together with an overview of the future developments.
*J Safranek, Experimental determination of storage ring optics using orbit response measurements, https://doi.org/10.1016/S0168-9002(97)00309-4

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS006

About •

Received ※ 19 May 2022 — Revised ※ 10 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 15 June 2022

Cite •

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

TUPOMS008

Lifetime Correction Using Fast-Off-Energy Response Matrix Measurements

sextupole, simulation, lattice, operation

1409

S.M. Liuzzo, N. Carmignani, L.R. Carver, L. Hoummi, T.P. Perron, B. Roche, S.M. White
ESRF, Grenoble, France

Following the measurements done at MAX-IV * we try to exploit for the ESRF-EBS Storage Ring (SR) off-energy response matrix measurement for the optimization of Touschek lifetime. The measurements performed with fast AC steerers on- and off-energy are analyzed and fitted producing an effective model including quadrupole and sextupole errors. Several alternatives to extrapolate sextupoles strengths for correction are compared in terms of lifetime. For the time being none of the corrections could produce better lifetime than the existing empirically optimized set of sextupoles.
*D.Olsson et al., Nonlinear optics from off-energy closed orbits, 10.1103/PhysRevAccelBeams.23.102803

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS008

About •

Received ※ 19 May 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 16 June 2022

Cite •

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

TUPOMS018

Error Analysis and Commissioning Simulation for the PETRA-IV Storage Ring

lattice, simulation, MMI, storage-ring

1442

T. Hellert, I.V. Agapov, S.A. Antipov, R. Bartolini, R. Brinkmann, Y.-C. Chae, D. Einfeld, M.A. Jebramcik, J. Keil
DESY, Hamburg, Germany

The upgrade of the PETRA-III storage ring into a diffraction limited synchrotron radiation source is nearing the end of its detailed technical design phase. We present a preliminary commissioning simulation for PETRA-IV demonstrating that the final corrected machines meet the performance design goals.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-TUPOMS018

About •

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

Cite •

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

WEPOST008

Optics Correction Strategy for Run 3 of the LHC

coupling, MMI, injection, quadrupole

1687

T.H.B. Persson, F.S. Carlier, A. Costa Ojeda, J. Dilly, V. Ferrentino, E. Fol, H. García Morales, M. Hofer, E.J. Høydalsvik, J. Keintzel, M. Le Garrec, E.H. Maclean, L. Malina, F. Soubelet, R. Tomás García, A. Wegscheider, L. van Riesen-Haupt
CERN, Meyrin, Switzerland
J.F. Cardona
UNAL, Bogota D.C, Colombia

After almost 4 years of shutdown the LHC is again operational in 2022. Experience from the previous Long Shutdown (LS) has shown that the local errors around the triplet magnets changed significantly and it is likely we will again see different errors in 2022. In the LHC there is an interplay between the linear and the nonlinear correction which can make the corrections difficult and time-consuming to find. In this article, we describe the measurements and corrections performed during the commissioning in 2022 in order to control both the linear and the nonlinear optics to high precision.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST008

About •

Received ※ 08 June 2022 — Revised ※ 25 June 2022 — Accepted ※ 04 July 2022 — Issue date ※ 10 July 2022

Cite •

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

WEPOST011

Studies on Top-Up Injection into the FCC-ee Collider Ring

injection, kicker, collider, lattice

1699

P.J. Hunchak, M.J. Boland
CLS, Saskatoon, Saskatchewan, Canada
M. Aiba
PSI, Villigen PSI, Switzerland
W. Bartmann, Y. Dutheil, M. Hofer, R.L. Ramjiawan, F. Zimmermann
CERN, Meyrin, Switzerland
M.J. Boland
University of Saskatchewan, Saskatoon, Canada

In order to maximize the luminosity production time in the FCC-ee, top-up injection will be employed. The positron and electron beams will be accelerated to the collision energy in the booster ring before being injected with either a small transverse or longitudinal separation to the stored beam. Using this scheme essentially keeps the beam current constant and, apart from a brief period during the injection process, collision data can be continuously acquired. Two top-up injection schemes, each with on- and off-momentum sub-schemes, viable for FCC-ee have been identified in the past and are studied in further detail to find a suitable design for each of the four operation modes of the FCC-ee. In this paper, injection straight optics, initial injection tracking studies and the effect on the stored beam are presented. Additionally, a basic proxy error lattice is introduced as a first step to studying injection into an imperfect machine.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST011

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022

Cite •

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

WEPOST015

Implementation of a Tune Sweep Slow Extraction with Constant Optics at MedAustron

extraction, simulation, betatron, operation

1715

P.A. Arrutia Sota, M.A. Fraser, B. Goddard, V. Kain, F.M. Velotti
CERN, Meyrin, Switzerland
P. Burrows
JAI, Oxford, United Kingdom
A. De Franco
QST Rokkasho, Aomori, Japan
F. Kuehteubl, M.T.F. Pivi, D.A. Prokopovich
EBG MedAustron, Wr. Neustadt, Austria

Conventional slow extraction driven by a tune sweep perturbs the optics and changes the presentation of the beam separatrix to the extraction septum during the spill. The constant optics slow extraction (COSE) technique, recently developed and deployed operationally at the CERN Super Proton Synchrotron to reduce beam loss on the extraction septum, was implemented at MedAustron to facilitate extraction with a tune sweep of operational beam quality. COSE fixes the optics of the extracted beam by scaling all machine settings with the beam rigidity following the extracted beam’s momentum. In this contribution the implementation of the COSE extraction technique is described before it is compared to the conventional tune sweep and operational betatron core driven cases using both simulations and recent measurements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST015

About •

Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 18 June 2022

Cite •

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

WEPOST017

Design of a Collimation Section for the FCC-ee

collimation, collider, operation, quadrupole

1722

M. Hofer, A. Abramov, R. Bruce, K. Oide, F. Zimmermann
CERN, Meyrin, Switzerland
M. Moudgalya, T. Pieloni
EPFL, Lausanne, Switzerland
K. Oide
KEK, Ibaraki, Japan

The design parameters of the FCC-ee foresee operation with a total stored beam energy of about 20 MJ, exceeding those of previous lepton colliders by almost two orders of magnitude. Given the inherent damage potential, a halo collimation system is studied to protect the machine hardware, in particular superconducting equipment such as the final focus quadrupoles, from sudden beam loss. The different constraints that led to dedicating one straight section to collimation will be outlined. In addition, a preliminary layout and optics for a collimation insertion are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST017

About •

Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 25 June 2022

Cite •

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

WEPOST023

Design of a Very Low Energy Beamline for NA61/SHINE

experiment, target, detector, radiation

1741

C.A. Mussolini, N. Charitonidis
CERN, Meyrin, Switzerland
P. Burrows, C.A. Mussolini
JAI, Oxford, United Kingdom
P. Burrows, C.A. Mussolini
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
Y. Nagai
Colorado University at Boulder, Boulder, Colorado, USA
E.D. Zimmerman
CIPS, Boulder, Colorado, USA

A new, low-energy branch is being designed for the H₂ beamline at the CERN North Experimental Area. This new low-energy branch would extend the capabilities of the current infrastructure enabling the study of particles in the low, 1 - 13 GeV/c, momentum range. The first experiment to profit from this new line will be NA61/SHINE (SPS Heavy Ion and Neutrino Experiment), a multi-purpose experiment studying hadron production in hadron-proton, hadron-nucleus and nucleus-nucleus collisions at the SPS. However, other future fixed target experiments or test-beam experiments installed in the downstream zones could also benefit from the low-energy particles provided. The proposed layout and expected performance of this line, along with estimates of particle rates, and considerations on the technical implementation of the beamline are presented in this contribution. A description on the instrumentation, which will enable particle-by-particle tagging, crucial for the experiments scope, is also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST023

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 29 June 2022 — Issue date ※ 05 July 2022

Cite •

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

WEPOST024

Physics Beyond Colliders: The Conventional Beams Working Group

experiment, proton, kaon, target

1745

C.A. Mussolini, D. Banerjee, A. Baratto Roldan, J. Bernhard, M. Brugger, N. Charitonidis, G.L. D’Alessandro, L. Gatignon, A. Gerbershagen, F. Metzger, R.P. Murphy, E.G. Parozzi, S.M. Schuh-Erhard, F.W. Stummer, M.W.U. Van Dijk
CERN, Meyrin, Switzerland
F. Metzger
HISKP, Bonn, Germany
R.P. Murphy, F.W. Stummer
Royal Holloway, University of London, Surrey, United Kingdom
C.A. Mussolini, F.W. Stummer
JAI, Oxford, United Kingdom
C.A. Mussolini
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
E.G. Parozzi
Universita Milano Bicocca, MILANO, Italy
E.G. Parozzi
INFN MIB, MILANO, Italy

The Physics Beyond Colliders initiative aims to exploit the full scientific potential of the CERN accelerator complex and its scientific infrastructure for particle physics studies, complementary to current and future collider experiments. Several experiments have been proposed to fully utilize and further advance the beam options for the existing fixed target experiments present in the North and East Experimental Areas of the CERN SPS and PS accelerators. We report on progress with the RF-separated beam option for the AMBER experiment, following a recent workshop on this topic. In addition we cover the status of studies for ion beams for the NA⁶⁰⁺ experiment, as well as of those for high intensity beams for Kaon physics and feebly interacting particle searches. With first beams available in 2021 after a CERN-wide long shutdown, several muon beam options were already tested for the NA64mu, MUonE and AMBER experiments.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOST024

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 10 July 2022

Cite •

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

WEPOPT007

First Interaction Region Local Coupling Corrections in the LHC Run 3

coupling, quadrupole, MMI, experiment

1838

F. Soubelet, T.H.B. Persson, R. Tomás García
CERN, Meyrin, Switzerland
Ö. Apsimon, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: This research is supported by the LIV. DAT Center for Doctoral Training, STFC and the European Organization for Nuclear Research
The successful operation of large scale particle accelerators depends on the precise correction of unavoidable magnetic field or magnet alignment errors present in the machine. During the LHC Run 2, local linear coupling in the interaction regions (IR) was shown to have a significant impact on the beam size, making its proper handling a necessity for Run 3 and the High Luminosity LHC (HL-LHC). A new approach to accurately minimise the local IR linear coupling based on correlated external variables such as the |C-| had been proposed, which relies on the application of a rigid waist shift in order to create an asymmetry in the IR optics. In this contribution, preliminary corrections from the 2021 beam test and the early 2022 commissioning are presented, as well as first results of the new method’s experimental configuration tests in the LHC Run 3 commissioning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT007

About •

Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 19 June 2022

Cite •

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

WEPOPT008

Supervised Machine Learning for Local Coupling Sources Detection in the LHC

coupling, quadrupole, network, simulation

1842

F. Soubelet, T.H.B. Persson, R. Tomás García
CERN, Meyrin, Switzerland
Ö. Apsimon, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: This research is supported by the LIV. DAT Center for Doctoral Training, STFC and the European Organization for Nuclear Research
Local interaction region (IR) linear coupling in the LHC has been shown to have a negative impact on beam size and luminosity, making its accurate correction for Run 3 and beyond a necessity. In view of determining corrections, supervised machine learning has been applied to the detection of linear coupling sources, showing promising results in simulations. An evaluation of different applied models is given, followed by the presentation of further possible application concepts for linear coupling corrections using machine learning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT008

About •

Received ※ 03 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 29 June 2022

Cite •

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

WEPOPT010

Progress on Action Phase Jump for LHC Local Optics Correction

simulation, quadrupole, operation, interaction-region

1850

J.F. Cardona, Y. Rodriguez Garcia
UNAL, Bogota D.C, Colombia
H. García Morales, M. Hofer, E.H. Maclean, T.H.B. Persson, R. Tomás García
CERN, Meyrin, Switzerland
Y. Rodriguez Garcia
UAN, Bogotá D.C., Colombia

The correction of the local optics at the Interaction Regions of the LHC is crucial to ensure a good performance of the machine. This is even more important for the future LHC upgrade, HL-LHC, where the optics is more sensitive to magnetic errors. For that reason, it is important to explore alternative techniques for local optics corrections. In this paper, we evaluate the performance of the Action Phase Jump method for optics correction in the LHC and the HL-LHC and explore ways to integrate this technique in regular operations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT010

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 18 June 2022

Cite •

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

WEPOPT012

MAD-X for Future Accelerators

coupling, closed-orbit, GUI, simulation

1858

T.H.B. Persson, H. Burkhardt, R. De Maria, L. Deniau, E.J. Høydalsvik, A. Latina, P.K. Skowroński, R. Tomás García, L. van Riesen-Haupt
CERN, Meyrin, Switzerland

The development of MAD-X was started more than 20 years ago and it still remains the main tool for single particle dynamics for both optics design, error studies as well as for operational model-based software at CERN. In this article, we outline some of the recent development of MAD-X and plans for the future. In particular, we focus on the development of the twiss module used to calculate optics functions in MAD-X which is based on first and second order matrices. These have traditionally been calculated as an expansion around the ideal orbit. In this paper, we describe explicitly how an expansion around the closed orbit can be employed instead, in order to get more precise results. We also describe the latest development of the beam-beam long range wire compensator in MAD-X, an element that has been implemented using the aforementioned approach.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT012

About •

Received ※ 08 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 01 July 2022

Cite •

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

WEPOPT016

Beam-Based Reconstruction of the Shielded Quench-Heater Fields for the LHC Main Dipoles

dipole, shielding, operation, injection

1874

L.C. Richtmann, L. Bortot, E. Ravaioli, C. Wiesner, D. Wollmann
CERN, Meyrin, Switzerland

Small orbit oscillations of the circulating particle beams have been observed immediately following quenches in the LHC’s superconducting main dipole magnets. Magnetic fields generated during the discharge into the quench heaters were identified as the cause. Since the resulting, shielded field inside the beam screen cannot be measured in-situ, the time evolution of the field has to be reconstructed from the measured beam excursions. In this paper, the field-reconstruction method using rotation in normalized phase space and the optimized fitting algorithm are described. The resulting rise times and magnetic field levels are presented for quench events that occurred during regular operation as well as for dedicated beam experiments. Finally, different approaches to model the shielding behavior of the beam screen are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT016

About •

Received ※ 16 May 2022 — Accepted ※ 13 June 2022 — Issue date ※ 26 June 2022

Cite •

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

WEPOPT017

First Optics Design for a Transverse Monochromatic Scheme for the Direct S-Channel Higgs Production at FCC-ee Collider

collider, positron, luminosity, site

1878

H.P. Jiang
Harbin Institute of Technology (HIT) , Harbin, People’s Republic of China
A. Faus-Golfe, Z.D. Zhang
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
K. Oide
KEK, Ibaraki, Japan
Z.D. Zhang
IHEP, Beijing, People’s Republic of China
Z.D. Zhang
UCAS, Beijing, People’s Republic of China
F. Zimmermann
CERN, Meyrin, Switzerland

The FCC-ee collider baseline foresees four different energy operation modes: Z, WW, H(ZH) and ttbar. An optional fifth mode, called s-channel Higgs production mode, could allow the measurement of the electron Yukawa coupling, in dedicated runs at 125 GeV centre-of-mass energy, provided that the centre-of-mass energy spread, can be reduced by at least an order of magnitude (5-10 MeV). The use of a special collision technique: a monochromatization scheme is one way to accomplish it. There are several methods to implement a monochromatization scheme. One method, named transverse monochromatization scheme, consists of introducing a dispersion different from zero but opposite sign for the two colliding beams at the Interaction Point (IP); In this paper we will report about the first attempt to design a new optics to implement a transverse monochromatic scheme for the FCC-ee Higgs production totally compatible with the standard mode of operation without dispersion at the IP.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT017

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 27 June 2022

Cite •

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

WEPOPT019

RHIC Blue Snake Blues

polarization, closed-orbit, operation, simulation

1881

F. Méot, E.C. Aschenauer, H. Huang, A. Marusic, V. Ptitsyn, V.H. Ranjbar, G. Robert-Demolaize, V. Schoefer
BNL, Upton, New York, USA

Funding: Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Two helical full snakes are used in both Blue and Yellow rings of RHIC collider, in order to preserve beam polarization during acceleration to collision energy and polarization lifetime at store. A snake in RHIC is comprised of four 2.4m long modules, powered by pair. During the startup of RHIC Run 22 in December 2021, two successive power dips have caused the 9 o’clock RHIC BlBrookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.ue ring snake to loose two of its four modules. In spite of this regrettable loss, it has been possible to maintain near 180deg snake precession, by proper powering of the remaining two modules, as well as, by re-tuning the 3 o’clock sister snake, vertical spin precession axis around the ring and spin tune 1/2. Determining these new settings, in order to salvage polarization with the handicapped Blue snake pair, has required series of numerical simulations, a brief overview is given here.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT019

About •

Received ※ 03 June 2022 — Revised ※ 17 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 07 July 2022

Cite •

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

WEPOPT035

Optics for Strong Hadron Cooling in EIC HSR-IR2

electron, hadron, kicker, cavity

1920

S. Peggs, W.F. Bergan, D. Bruno, Y. Gao, D. Holmes, R.F. Lambiase, C. Liu, H. Lovelace III, G.J. Mahler, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, E. Wang, D. Weiss, D. Xu
BNL, Upton, New York, USA
S.V. Benson, T.J. Michalski
JLab, Newport News, Virginia, USA
F. Micolon
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC001 2704, and by Jefferson Science Associates, LLC under Contract No. DE-AC05-06OR23177.
Insertion Region 2 (IR2) of the Relativistic Heavy Ion Collider will be modified to accommodate a Strong Hadron Cooling facility in the Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC). This paper describes the current proof-of-principle design of HSR-IR2 - layout, optical performance, design methodology, and engineering requirements. It also describes the challenges and opportunities in the future development of the HSR-IR2 design, in order to further optimize Strong Hadron Cooling performance.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT035

About •

Received ※ 02 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 18 June 2022 — Issue date ※ 06 July 2022

Cite •

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

WEPOPT043

Dynamic Aperture of the EIC Electron Storage Ring

sextupole, lattice, quadrupole, electron

1950

Y.M. Nosochkov, Y. Cai
SLAC, Menlo Park, California, USA
J.S. Berg, J. Kewisch, Y. Li, D. Marx, C. Montag, S. Tepikian, H. Witte
BNL, Upton, New York, USA
G.H. Hoffstaetter, J.E. Unger
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by the Department of Energy Contract DE-AC02-76SF00515, by Brookhaven Science Associates, LLC under Contract DE-SC0012704, and by the Ernest Courant Traineeship in Accelerator Science and Technology Award No. DE-SC0020375.
The Electron Ion Collider (EIC) is under design at Brookhaven National Laboratory. The EIC aims at providing high luminosity and high polarization collisions for a large range of beam energies. Dynamic aperture (DA) of the EIC Electron Storage Ring (ESR) must be sufficiently large in both transverse and momentum dimensions. The latter is a challenge due to low-beta optics in up to two interaction regions (IR). We have developed an advanced technique for efficient non-linear chromaticity compensation compatible with the different ESR lattice configurations at different energies. The solution for the most challenging lattice with two IRs at 18 GeV is presented. The lattice is then evaluated with magnet errors, where the error tolerances are determined for reaching the desired DA.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT043

About •

Received ※ 08 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 01 July 2022

Cite •

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

WEPOPT047

Beam Optics of the Injection/Extraction and Beam Transfer in the Electron Rings of the EIC Project

injection, extraction, electron, kicker

1964

N. Tsoupas, D. Holmes, C. Liu, C. Montag, V. Ptitsyn, V.H. Ranjbar, J. Skaritka, J.E. Tuozzolo, E. Wang, F.J. Willeke
BNL, Upton, New York, USA
B. Bhandari
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-SC0012704 with the U.S. Department of Energy.
The Electron-Ion Collider (EIC) project* has been approved by the Department of Energy to be built at the site of Brookhaven National Laboratory (BNL). The goal of the project is the collision of energetic (of many GeV/amu) ion species with electron bunches of energies up to 18 GeV. The EIC includes two electron rings, the Rapid Cycling Synchrotron (RCS) which accelerates the electron beam up to 18 GeV, and the Electron Storage Ring (ESR) which stores the electron beam for collisions with hadron beam, both to be installed in the same tunnel as the Hadron Storage Ring (HSR). This paper discusses the layout and the beam optics of the injection/extraction beam lines the electron rings and the beam optics of the transfer line from the RCS to the ESR ring.
* https://www.bnl.gov/eic/

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT047

About •

Received ※ 05 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 14 June 2022 — Issue date ※ 23 June 2022

Cite •

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

WEPOPT060

Controlling Landau Damping via Feed-Down From High-Order Correctors in the LHC and HL-LHC

target, simulation, MMI, controls

1995

J. Dilly, E.H. Maclean, R. Tomás García
CERN, Meyrin, Switzerland

Funding: This work has been supported by the HiLumi Project and been sponsored by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Re-search.
Amplitude detuning measurements in the LHC have shown that a significant amount of detuning is generated in Beam 1 via feed-down from decapole and dodecapole field errors in the triplets of the experiment insertion regions, while in Beam 2 this detuning is negligible. In this study, we investigate the cause of this behavior and we attempt to find corrections that use the feed-down from the nonlinear correctors in the insertion region for amplitude detuning.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT060

About •

Received ※ 07 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 06 July 2022

Cite •

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

WEPOPT061

A Flexible Nonlinear Resonance Driving Term Based Correction Algorithm with Feed-Down

luminosity, resonance, dipole, insertion

1999

J. Dilly, R. Tomás García
CERN, Meyrin, Switzerland

Funding: This work has been supported by the HiLumi Project and been sponsored by the Wolfgang Gentner Programme of the German Federal Ministry of Education and Re-search.
The optics in the insertion regions of the LHC and its upgrade project the High Luminosity LHC are very sensitive to local magnetic errors, due to the extremely high beta-functions. In collision optics, the non-zero closed orbit in the same region leads to a "feed-down" of high-order errors to lower orders, causing additional effects detrimental to beam lifetime. An extension to the well-established method for correcting these errors by locally suppressing resonance driving terms has been undertaken, not only taking this feed-down into account, but also adding the possibility of utilizing it such that the powering of higher-order correctors will compensate for lower order errors. Existing correction schemes have also operated on the assumption of (anti-)symmetric beta-functions of the optics in the two rings. This assumption can fail for a multitude of reasons, such as inherently asymmetric optics and unevenly distributed errors. In this respect, an extension of this correction scheme has been developed, removing the need for symmetry by operating on the two separate optics of the beams simultaneously.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOPT061

About •

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

Cite •

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

WEPOTK006

Proton Beamline Simulations for the High Intensity Muon Beamline at PSI

target, simulation, proton, cyclotron

2036

M. Haj Tahar, D.C. Kiselev, A. Knecht, D. Laube, D. Reggiani, J. Snuverink, V. Talanov
PSI, Villigen PSI, Switzerland

The High Intensity Proton Accelerator (HIPA) cyclotron at the Paul Scherrer Institut (PSI) delivers 590 MeV CW proton beam with a maximum power of 1.42 MW. After extraction, the beam is transferred in a 120 m long channel towards two target stations (TgM and TgE) before depositing its remaining power at the spallation target SINQ for neutron production. As part of the High Intensity Muon Beamline (HIMB) feasibility study, which belongs to the IMPACT (Isotope and Muon Production using Advanced Cyclotron and Target technologies) initiative, the first of these targets will be replaced with a thicker one and its geometry opti- mized thereby specifically boosting the emission of surface muons. In order to assess the impact of the changes on the proton beamline, BDSIM/GEANT4 simulations were performed with the realistic technical design of the target insert, the collimation system was redesigned and the power depositions were benchmarked with MCNP6. In this paper, we discuss the major changes and challenges for HIMB as well as the key considerations in redesigning the optics of the high power beam in the vicinity of the target stations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK006

About •

Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 27 June 2022

Cite •

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

WEPOTK014

Hadron Storage Ring 4 O’clock Injection Design and Optics for the Electron-Ion Collider

injection, electron, septum, dipole

2068

H. Lovelace III, J.S. Berg, D. Bruno, C. Cullen, K.A. Drees, W. Fischer, X. Gu, R.C. Gupta, D. Holmes, R.F. Lambiase, C. Liu, C. Montag, S. Peggs, V. Ptitsyn, G. Robert-Demolaize, R. Than, J.E. Tuozzolo, M. Valette, D. Weiss
BNL, Upton, New York, USA
B. Bhandari, F. Micolon, N. Tsoupas, S. Verdú-Andrés
Brookhaven National Laboratory (BNL), Electron-Ion Collider, Upton, New York, USA
B.R. Gamage, T. Satogata, W. Wittmer
JLab, Newport News, Virginia, USA

The Hadron Storage Ring (HSR) of the Electron-Ion Collider (EIC) will accelerate protons and heavy ions up to a proton energy of 275 GeV and an Au⁺⁷⁹ 110 GeV/u to collide with electrons of energies up to 18 GeV. To accomplish the acceleration process, the hadrons are pre-accelerated in the Alternating Gradient Synchrotron (AGS), extracted, and transferred to HSR for injection. The planned area for injection is the current Relativistic Heavy Ion Collider (RHIC) 4 o’clock straight section. To inject hadrons, a series of modifications must be made to the existing RHIC 4 o’clock straight section to accommodate for the 20 new ~18 ns injection kickers and a new injection septum, while providing sufficient space and proper beam conditions for polarimetry equipment. These modifications will be discussed in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK014

About •

Received ※ 02 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 21 June 2022

Cite •

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

WEPOTK034

LHC Beam Collimation During Extended β*-Levelling in Run 3

collimation, luminosity, operation, experiment

2138

F.F. Van der Veken, R. Bruce, M. Hostettler, D. Mirarchi, S. Redaelli
CERN, Meyrin, Switzerland

During the third operational Run of the Large Hadron Collider at CERN, starting in 2022, the bunch population will be increased to unprecedented levels requiring to deploy β^*-levelling of the luminosity over a wide range of values to cope with the limitations imposed by event pile-up at the experiments and heat load on the triplets induced by collision debris. During this levelling, both beam optics and orbit change in various areas of the ring, in particular around the high-luminosity experiments, where several collimators are installed. This requires adapting the collimation system settings adequately, in particular for the tertiary collimators (TCTs) that protect the inner-triplet magnets. To this end, two strategies are considered: keeping collimators at fixed physical openings while shifting their centres following the beam orbit, or varying also the collimator openings. The latter strategy is planned when the larger optics range will be deployed. In this paper, we investigate several loss scenarios at the TCTs in different steps of the levelling, and present the proposed collimator settings during Run 3.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOTK034

About •

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

Cite •

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

WEPOMS031

Light Path Construction for an Optical Stochastic Cooling Stability Test at the Cornell Electron Storage Ring

radiation, experiment, synchrotron, feedback

2315

S.J. Levenson, M.B. Andorf, I.V. Bazarov, D.C. Burke, J.M. Maxson, D.L. Rubin, S. Wang
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: This work was supported by the U.S. National Science Foundation under Award PHY-1549132, the Center for Bright Beams and NYSTAR award C150153.
An experiment at the Cornell Electron Storage Ring (CESR) to test the optical path-length stability of a bypass suitable for Optical Stochastic Cooling (OSC) is being pursued. The approximately 80 m light path for this experiment has been assembled, and synchrotron light has been successfully propagated from both sources. A feedback system based on an Electro-Optic Modulator (EOM) to correct the path-error accumulated in both the light and particle path has been table-top tested. We present on the design and construction of the light optics for the OSC stability experiment at CESR.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS031

About •

Received ※ 08 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 21 June 2022 — Issue date ※ 03 July 2022

Cite •

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

WEPOMS035

Harpy: A Fast, Simple and Accurate Harmonic Analysis with Error Propagation

betatron, synchrotron, operation, coupling

2326

L. Malina
DESY, Hamburg, Germany

Traditionally, in the accelerator physics field, accurate harmonic analysis has been performed by iteratively interpolating the result of Fast Fourier Transform (FFT) in the frequency domain. Such an approach becomes computationally demanding when relatively small effects are being studied, which is especially evident in the typical example of harmonic analysis of turn-by-turn beam position monitor data, i.e. many correlated but noisy signals. A new harmonic analysis algorithm, called Harpy, is about an order of magnitude faster than other methods, while often being also more accurate. Harpy combines standard techniques such as zero-padded FFT and noise-cleaning based on singular value decomposition. This combination also allows estimating errors of phases and amplitudes of beam-related harmonics calculated from cleaned data.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS035

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 20 June 2022

Cite •

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

WEPOMS043

UFO, a GPU Code Tailored Toward MBA Lattice Optimization

GPU, lattice, electron, simulation

2346

M. Carlà, M. Canals
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain

The complexity of multi-bend achromatic optics is such that computational tools performance has become a dominant factor in the design process a last generation synchrotron light source. To relieve the problem a new code (UFO) tailored toward performance was developed to assist the design of the ALBA-II optics. Two main strategies contribute to the performance of UFO: the execution flow follows a data parallel paradigm, well suited for GPU execution; the use of a just-in-time compiler allows to simplify the computation whenever the lattice allows for it. At the core of UFO lies a parallel tracking routine structured for parallel simulation of optics which differs in some parameters, such as magnet strength or alignment, but retains the same element order, reflecting the scenario found in optimization processes, or when dealing with magnetic or alignment errors. Such an approach allows to take advantage of GPUs which yield the best performance when running thousands of parallel threads. Moreover UFO is not limited to tracking. A few modules that rely on the same tracking routine allow for the fast computation of dynamic and momentum aperture, closed orbit and linear optics.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS043

About •

Received ※ 07 June 2022 — Revised ※ 16 June 2022 — Accepted ※ 19 June 2022 — Issue date ※ 21 June 2022

Cite •

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

WEPOMS047

Automated Design and Optimization of the Final Cooling for a Muon Collider

emittance, simulation, collider, solenoid

2358

E. Fol, D. Schulte, B. Stechauner
CERN, Meyrin, Switzerland
C.T. Rogers
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
J. Schieck
HEPHY, Wien, Austria

The desired beam emittance for a Muon collider is several orders of magnitude less than the one of the muon beams produced at the front-end target. Ionization cooling has been demonstrated as a suitable technique for the reduction of the muon beam emittance. Final cooling, as one of the most critical stages of the muon collider complex, necessitates careful design and optimization in order to control the beam dynamics and ensure efficient emittance reduction. We present an optimization framework based on ICool simulation code and application of different optimization algorithms, to automatize the choice of optimal initial muon beam parameters and simultaneous tuning of numerous final cooling components.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS047

About •

Received ※ 07 June 2022 — Revised ※ 14 June 2022 — Accepted ※ 23 June 2022 — Issue date ※ 03 July 2022

Cite •

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

WEPOMS052

Impacts of an ATS Lattice on EIC Dynamic Aperture

sextupole, lattice, electron, collider

2373

J.E. Unger, J.A. Crittenden, G.H. Hoffstaetter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
D. Marx
BNL, Upton, New York, USA

The Electron-Ion Collider (EIC) project at Brookhaven National Laboratory has explored strategies for increasing the energy aperture of the Electron Storage Ring (ESR) to meet the goal of 1\% for the 90 degree lattice at 18 GeV. Current strategies use a four sextupole family per arc correction scheme to increase the energy aperture and to keep the transverse aperture sufficiently large as well. A scheme called Achromatic Telescopic Squeezing (ATS), first introduced for the Large Hadron Collider, introduces a beta-beat into select arcs, allowing dynamic aperture optimizations with different sextupole strengths. The ATS scheme’s mix of some higher beta-function and some lower sextupole strengths in the arcs has the potential to increase the energy aperture. Basic chromatic corrections and numeric optimizations were used to compare the ATS optics to a non-ATS scheme. In all cases, the ATS scheme performed similarly or better than the more common schemes. However, this increase in energy aperture from the ATS optics also has negative effects, such as an increase in emittance which poses complications for the current ESR design.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-WEPOMS052

About •

Received ※ 08 June 2022 — Revised ※ 13 June 2022 — Accepted ※ 15 June 2022 — Issue date ※ 05 July 2022

Cite •

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

THPOPT006

Beam Dynamics Observations at Negative Momentum Compaction Factors at KARA

sextupole, damping, synchrotron, operation

2570

P. Schreiber, M. Brosi, B. Härer, A. Mochihashi, A.-S. Müller, A.I. Papash, R. Ruprecht, M. Schuh
KIT, Karlsruhe, Germany

Funding: We are supported by the DFG-funded "Karlsruhe School of Elementary and Astroparticle Physics: Science and Technology" and European Union’s Horizon 2020 research and innovation programme (No 730871)
For the development of future synchrotron light sources new operation modes often have to be considered. One such mode is the operation with a negative momentum compaction factor to provide the possibility of increased dynamic aperture. For successful application in future light sources, the influence of this mode has to be investigated. At the KIT storage ring KARA (Karlsruhe Research Accelerator), operation with negative momentum compaction has been implemented and the dynamics can now be investigated. Using a variety of high-performance beam diagnostics devices it is possible to observe the beam dynamics under negative momentum compaction conditions. This contribution presents different aspects of the results of these investigations in the longitudinal and transversal plane.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT006

About •

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

Cite •

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

THPOPT013

Emittance Reduction with the Variable Dipole for the ELETTRA 2.0 Ring

dipole, emittance, lattice, damping

2586

A. Poyet, Y. Papaphilippou
CERN, Meyrin, Switzerland
M.A. Domínguez, F. Toral
CIEMAT, Madrid, Spain
R. Geometrante, E. Karantzoulis
Elettra-Sincrotrone Trieste S.C.p.A., Basovizza, Italy
R. Geometrante
KYMA, Trieste, Italy

ELETTRA is a 2/2.4 GeV third-generation electron storage ring, located near Trieste, Italy. In view of a substantial increase of the machine performance in terms of brilliance, the so-called ELETTRA 2.0 upgrade is currently on-going. This upgrade is based on a 6-bends achromat, four dipoles of which having a longitudinally variable field. So far, those dipoles are foreseen to provide a field with a two step profile. The VAriable Dipole for the ELETTRA Ring (VADER) task, driven by the I.FAST European project, aims at developing a new dipole design based on a trapezoidal shape of the bending radius, which would allow for a further reduction of the horizontal emittance. A prototype of this magnet should be designed by the CIEMAT laboratory and built by KYMA company. This paper discusses the new dipole field specification and describes the corresponding optics optimization that was performed in order to reduce at best the emittance of the ELETTRA ring.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT013

About •

Received ※ 07 June 2022 — Revised ※ 09 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 03 July 2022

Cite •

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

THPOPT016

Commissioning Simulations for the DIAMOND-II Upgrade

MMI, injection, storage-ring, quadrupole

2598

H.C. Chao, R.T. Fielder, J. Kallestrup, I.P.S. Martin, B. Singh
DLS, Oxfordshire, United Kingdom

The Diamond-II storage ring, compared to Diamond, improves the natural beam emittance from 2.7 nm to 160 pm and the beam energy from 3 to 3.5 GeV. The number of straight sections is also doubled from 24 to 48 thanks to the modified hybrid six-bend-achromat lattice. To reduce the impact on the existing science program, the dark time period must be minimised. To assist in this aim, storage ring commissioning simulations have been carried out to predict and resolve possible issues. These studies include beam commissioning starting from on-axis first-turn beam threading up to beam based alignment and full linear optics correction with stored beam. The linear optics corrections with insertion devices are also included. The machine characterisations at different stages are compared. Considerations on realistic chamber limitations, error definitions and some commissioning strategies are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT016

About •

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

Cite •

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

THPOPT068

Linear Canonical Transform Library for Fast Coherent X-Ray Wavefront Propagation

radiation, synchrotron, operation, synchrotron-radiation

2759

B. Nash, D.T. Abell, P. Moeller, I.V. Pogorelov
RadiaSoft LLC, Boulder, Colorado, USA
N.B. Goldring
STATE33 Inc., Portland, Oregon, USA

Funding: This work is supported by the US Department of Energy, Office of Basic Energy Sciences under Award No. DE-SC0020593.
X-ray beamlines are essential components of all synchrotron light sources, transporting radiation from the stored electron beam passing from the source to the sample. The linear optics of the beamline can be captured via an ABCD matrix computed using a ray tracing code. Once the transport matrix is available, one may then include diffraction effects and arbitrary wavefront structure by using that same information in a Linear Canonical Transform (LCT) applied to the initial wavefront. We describe our implementation of a Python-based LCT library for 2D synchrotron radiation wavefronts. We have thus far implemented the separable case and are in the process of implementing algorithms for the non-separable case. Rectangular apertures are also included. We have tested our work against corresponding wavefront computations using The Synchrotron Radiation Workshop (SRW) code. LCT vs. SRW timing and benchmark comparisons are given for undulator and bending magnet beamlines. This algorithm is being included in the Sirepo implementation of the Shadow ray tracing code. Finally, we describe our plans for application to partially coherent radiation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOPT068

About •

Received ※ 15 June 2022 — Revised ※ 15 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 01 July 2022

Cite •

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

THPOTK063

Open Source Software to Simulate Ti:Sapphire Amplifiers

laser, simulation, photon, experiment

2925

D.L. Bruhwiler, D.T. Abell, B. Nash
RadiaSoft LLC, Boulder, Colorado, USA
Q. Chen, C.G.R. Geddes, C. Tóth, J. van Tilborg
LBNL, Berkeley, USA
N.B. Goldring
STATE33 Inc., Portland, Oregon, USA

Funding: This work is supported by the US Department of Energy, Office of High Energy Physics under Award Numbers DE-SC0020931 and DE-AC02-05CH11231.
The design of next-generation PW-scale fs laser systems, including scaling to kHz rates and development of new laser gain media for efficiency, will require parallel multiphysics simulations with realistic errors and nonlinear optimization. There is currently a lack of broadly available modeling software that self-consistently captures the required physics of gain, thermal loading and lensing, spectral shaping, and other effects required to quantitatively design such lasers.* We present initial work towards an integrated multiphysics capability for modeling pulse amplification in Ti:Sa lasers. All components of the software suite are open source. The Synchrotron Radiation Workshop (SRW)** is being used for physical optics, together with Python utilities. The simulations are being validated against experiments.
* R. Falcone et al., Brightest Light Initiative Workshop Report (2019).
** https://github.com/ochubar/srw

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOTK063

About •

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

Cite •

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

THPOMS001

TURBO: A Novel Beam Delivery System Enabling Rapid Depth Scanning for Charged Particle Therapy

proton, dipole, controls, multipole

2929

J.S.L. Yap, S.L. Sheehy
The University of Melbourne, Melbourne, Victoria, Australia
R.B. Appleby, H.X.Q. Norman, A.F. Steinberg
UMAN, Manchester, United Kingdom

Charged particle therapy (CPT) is a well-established modality of cancer treatment and is increasing in worldwide presence due to improved accelerator technology and modern techniques. The beam delivery system (BDS) determines the overall timing and beam shaping capabilities, but is restricted by the energy variation speed: energy layer switching time (ELST). Existing treatment beamlines have a ±1% momentum acceptance range, needing time to change the magnetic fields as the beam is delivered in layers at various depths across the tumour volume. Minimising the ELST can enable the delivery of faster, more effective and advanced treatments but requires an improved BDS. A possibility for this could be achieved with a design using Fixed Field Alternating Gradient (FFA) optics, enabling a large energy acceptance to rapidly transport beams of varying energies. A scaled-down, novel system - Technology for Ultra Rapid Beam Operation (TURBO) - is being developed at the University of Melbourne, to explore the potential of rapid depth scanning. Initial simulation studies, beam and field measurements, project plans and clinical considerations are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS001

About •

Received ※ 20 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 30 June 2022

Cite •

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

THPOMS002

Gantry Beamline and Rotator Commissioning at the Medaustron Ion Therapy Center

MMI, proton, quadrupole, radiation

2933

M.T.F. Pivi, L. Adler, G. Guidoboni, G. Kowarik, C. Kurfürst, C. Maderböck, D.A. Prokopovich, I. Strašík
EBG MedAustron, Wr. Neustadt, Austria
G. Kowarik
GKMT Consulting, Consulting and Project Management, Vienna, Austria
M. Pavlovič
STU, Bratislava, Slovak Republic
M.G. Pullia
CNAO Foundation, Pavia, Italy
V. Rizzoglio
PSI, Villigen PSI, Switzerland

The MedAustron Particle Therapy Accelerator located in Austria, delivers proton beams in the energy range 60-250 MeV/n and carbon ions 120-400 MeV/n for medical treatment in two irradiation rooms, clinically used for tumor therapy. Proton beams up to 800 MeV/n are also provided to a room dedicated to scientific research. Over the last two years, in parallel to clinical operations, we have completed the installation and commissioning of the gantry beam line in a dedicated room, ready for the first patient treatment in early 2022. In this manuscript, we provide an overview of the MedAustron gantry beam commissioning including the world-wide first ’rotator’ system, a rotating beamline located upstream of the gantry and used to match the slowly extracted non-symmetric beams into the coordinate system of the gantry. Using the rotator, all beam parameters at the location of the patient become independent of the gantry rotation angle. Furthermore, both the gantry and the high energy transfer line optics had to be redesigned and adapted to the rotator-mode of operation. A review of the beam commissioning including technical solutions, main results and reference measurements is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS002

About •

Received ※ 08 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 04 July 2022

Cite •

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

THPOMS011

Beam Optics Studies for a Novel Gantry for Hadrontherapy

dipole, quadrupole, operation, hadrontherapy

2962

E. Felcini, G. Frisella, A. Mereghetti, M.G. Pullia, S. Savazzi
CNAO Foundation, Pavia, Italy
E. Benedetto
SEEIIST, Geneva, Switzerland
M.T.F. Pivi
EBG MedAustron, Wr. Neustadt, Austria

Funding: This study was (partially) supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101008548 (HITRIplus).
The design of smaller and less costly gantries for carbon ion particle therapy represents a major challenge to the diffusion of this treatment. Here we present the work done on the linear beam optics of possible gantry layouts, differing for geometry, momentum acceptance, and magnet technology, which share the use of combined function superconducting magnets with a bending field of 4T. We performed parallel-to-point and point-to-point optics matching at different magnification factors to provide two different beam sizes at the isocenter. Moreover, we considered the orbit distortion generated by magnet errors and we introduced beam position monitors and correctors. The study, together with considerations on the criteria for comparison, is the basis for the design of a novel and compact gantry for hadrontherapy.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS011

About •

Received ※ 20 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 16 June 2022 — Issue date ※ 30 June 2022

Cite •

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

THPOMS012

Explorative Studies of an Innovative Superconducting Gantry

dipole, superconducting-magnet, quadrupole, hadrontherapy

2966

M.G. Pullia, M. Donetti, E. Felcini, G. Frisella, A. Mereghetti, A. Mirandola, A. Pella, S. Savazzi
CNAO Foundation, Pavia, Italy
E. Benedetto
SEEIIST, Geneva, Switzerland
L. Dassa, M. Karppinen, D. Perini, D. Tommasini, M. Vretenar
CERN, Meyrin, Switzerland
E. De Matteis, L. Rossi
INFN/LASA, Segrate (MI), Italy
C. Kurfürst, M.T.F. Pivi, M. Stock
EBG MedAustron, Wr. Neustadt, Austria
S. Mariotto, M. Prioli
INFN-Milano, Milano, Italy
L. Piacentini, A. Ratkus, T. Torims, J. Vilcans
Riga Technical University, Riga, Latvia
L. Sabbatini, A. Vannozzi
LNF-INFN, Frascati, Italy
S. Uberti
Università di Brescia, Brescia, Italy

Funding: This study was (partially) supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement no. 101008548 (HITRIplus).
The Heavy Ion Therapy Research Integration plus (HITRIplus) is a European project that aims to integrate and propel research and technologies related to cancer treatment with heavy ions beams. Among the ambitious goals of the project, a specific work package includes the design of a gantry for carbon ions, based on superconducting magnets. The first milestone to achieve is the choice of the fundamental gantry parameters, namely the beam optics layout, the superconducting magnet technology, and the main user requirements. Starting from a reference 3T design, the collaboration widely explored dozens of possible gantry configurations at 4T, aiming to find the best compromise in terms of footprint, capital cost, and required R&D. We present here a summary of these configurations, underlying the initial correlation between the beam optics, the mechanics, and the main superconducting dipoles design: the bending field (up to 4 T), combined function features (integrated quadrupole), magnet aperture (up to 90 mm), and angular length (30°-45°). The resulting main parameters are then listed, compared, and used to drive the choice of the best gantry layout to be developed in HITRIplus.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS012

About •

Received ※ 20 May 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)

THPOMS018

Study of Coil Configuration and Local Optics Effects for the GaToroid Ion Gantry Design

focusing, hadrontherapy, hadron, radiation

2984

E. Oponowicz, L. Bottura, Y. Dutheil, A. Gerbershagen, A. Haziot
CERN, Meyrin, Switzerland

Funding: Project co-funded by the CERN Budget for Knowledge Transfer to Medical Applications.
GaToroid, a novel configuration for hadron therapy gantry, is based on superconducting coils that gen- erate a toroidal magnetic field to deliver the beam onto the patient. Designing the complex GaToroid coils requires careful consideration of the local beam optical effects. We present a Python-based tool for charged particle transport in complex electromagnetic fields. The code implements fast tracking in arbitrary three-dimensional field maps, and it is not limited to specific or regular reference trajectories, as is generally the case in accelerator physics. The tool was used to characterise the beam behaviour inside the GaToroid system. It automatically determines the reference trajectories in the symmetry plane and analyses three-dimensional beam dynamics around these trajectories. Beam optical parameters in the field region were compared for various magnetic configurations of GaToroid. This paper introduces the new tracker and shows the benchmarking results. Furthermore, first- order beam optics studies for different arrangements demonstrate the main code features and serve for the design optimisation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS018

About •

Received ※ 19 May 2022 — Revised ※ 16 June 2022 — Accepted ※ 17 June 2022 — Issue date ※ 23 June 2022

Cite •

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

THPOMS020

Beam Optics Study for a Potential VHEE Beam Delivery System

scattering, electron, quadrupole, dipole

2992

C.S. Robertson, P. Burrows
JAI, Oxford, United Kingdom
M. Dosanjh, A. Gerbershagen, A. Latina
CERN, Meyrin, Switzerland

VHEE (Very High Energy Electron) therapy can be superior to conventional radiotherapy for the treatment of deep seated tumours, whilst not necessarily requiring the space and cost of proton or heavy ion facilities. Developments in high gradient RF technology have allowed electrons to be accelerated to VHEE energies in a compact space, meaning that treatment could be possible with a shorter linac. A crucial component of VHEE treatment is the transfer of the beam from accelerator to patient. This is required to magnify the beam to cover the transverse extent of the tumour, whilst ensuring a uniform beam distribution. Two principle methodologies for the design of a compact transfer line are presented. The first of these is based upon a quadrupole lattice and optical magnification of beam size. A minimisation algorithm is used to enforce certain criteria on the beam distribution at the patient, defining the lattice through an automated routine. Separately, a dual scattering-foil based system is also presented, which uses similar algorithms for the optimisation of the foil geometry in order to achieve the desired beam shape at the patient location.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS020

About •

Received ※ 19 May 2022 — Accepted ※ 16 June 2022 — Issue date ※ 18 June 2022

Cite •

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

THPOMS024

A Novel Intensity Compensation Method to Achieve Energy Independent Beam Intensity at the Patient Location for Cyclotron Based Proton Therapy Facilities

cyclotron, proton, emittance, beam-losses

3004

V. Maradia, A.L. Lomax, D. Meer, S. Psoroulas, D.C. Weber
PSI, Villigen PSI, Switzerland
V. Maradia
ETH, Zurich, Switzerland

Funding: This work is supported by a PSI inter-departmental funding initiative (Cross)
In cyclotron-based proton therapy facilities, an energy selection system is typically used to lower beam energy from the fixed value provided by the accelerator (250/230MeV) to the one needed for the treatment (230-70MeV). Such a system has drawback of introducing an energy-dependent beam current at the patient location, resulting in energy-dependent beam intensity ratios of about 10³ between high and low energies. This complicates treatment delivery and challenges patient safety systems. As such, we propose the use of a dual-energy degrader method that can reduce beam intensity for high-energy beams. The first degrader is made of high Z material and the second is made of low Z material and are placed next to each other. For high energies (230-180MeV), we use only first degrader to increase beam emittance after degrader and thus lose intensity in emittance selection collimators. For intermediate energy beams (180-100MeV) we use the combination of both degraders, whereas for low energy beams (100-70MeV), only the second degrader limits the increase in emittance. With this approach, energy-independent beam intensities can be achieved, whilst localizing beam losses around the degrader.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS024

About •

Received ※ 16 May 2022 — Revised ※ 13 June 2022 — Accepted ※ 13 June 2022 — Issue date ※ 14 June 2022

Cite •

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

THPOMS025

A Novel Method of Emittance Matching to Increase Beam Transmission for Cyclotron Based Proton Therapy Facilities: Simulation Study

scattering, emittance, proton, cyclotron

3007

V. Maradia, A.L. Lomax, D. Meer, S. Psoroulas, J.M. Schippers, D.C. Weber
PSI, Villigen PSI, Switzerland
V. Maradia
ETH, Zurich, Switzerland

Funding: This work is supported by a PSI inter-departmental funding initiative (Cross)
In proton therapy, high dose rates can reduce treatment delivery times, allowing for efficient mitigation of tumor motion and increased patient throughput. With cyclotrons, however, high dose rates are difficult to achieve for low-energies as, typically, the emittance after the degrader is matched in both transversal planes using circular collimators, which does not provide an optimal matching to the acceptance of the following beamline. Transmission can however be substantially improved by transporting maximum acceptable emittances in both orthogonal planes, but at the cost of gantry angle-dependent beam shapes at isocenter. Here we demonstrate that equal emittances in both planes can be recovered at the gantry entrance using a thin scattering foil, thus ensuring gantry angle-independent beam shapes at the isocenter. We demonstrate experimentally that low-energy beam transmission can be increased by a factor of 3 using this approach compared to the currently used beam optics, whilst gantry angle-independent beam shapes are preserved. We expect that this universal approach could also bring a similar transmission improvement in other cyclotron-based proton therapy facilities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2022-THPOMS025

About •

Received ※ 16 May 2022 — Revised ※ 11 June 2022 — Accepted ※ 28 June 2022 — Issue date ※ 28 June 2022

Cite •

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