IPAC2019 - List of Keywords (septum)

Paper	Title	Other Keywords	Page
MOPTS030	Characterisation and First Beam Line Tests of the Elbe Stripline Kicker	kicker, laser, neutron, simulation	918
	Ch. Schneider, A. Arnold, M. Freitag, J. Hauser, P. Michel HZDR, Dresden, Germany
	The linac based CW electron accelerator ELBE operates different secondary beamlines one at a time. For the future different end stations should be served simultaneously, hence specific bunch patterns have to be kicked into different beam-lines. The variability of the bunch pattern and the frequency resp. switching time are one of the main arguments for a stripline-kicker. A design with two tapered active electrodes and two ground fenders was optimized in time and frequency domain with the software package CST. From that a design has been transferred into a construction and was manufactured. The prototype has been tested in the laboratory and installed in the ELBE beam line. The presentation summarises the recent results and the first beam line test.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPTS030
About •	paper received ※ 10 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
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TUPTS028	Extraction System of Upgraded AVF Cyclotron of RCNP	proton, extraction, cyclotron, injection	1993
	M. Nakao, M. Fukuda, S. Hara, T. Hara, K. Hatanaka, K. Kamakura, H. Kanda, H.W. Koay, S. Morinobu, Y. Morita, K. Nagayama, T. Saito, K. Takeda, H. Tamura, Y. Yasuda, T. Yorita RCNP, Osaka, Japan
	The AVF cyclotron of RCNP have been utilized for the purposes of basic research in physics, RI production for medicine and industrial applications as well as injector of ring cyclotron. Increasing beam intensity without decreasing beam quality can make improvements in all purposes. The improvement and repair of the AVF cyclotron are being carried out currently. We designed the new LEBT, injection, acceleration and extraction systems and we report on the extraction system here. High extraction efficiency is indispensable when increasing the beam intensity since beam loss causes activation of apparatus. New extraction system consists of deflector electrodes and two gradient correctors and probes. One gradient corrector causes a horizontally focus effect on the beam and the other causes horizontally defocus effect to avoid spreading of the beam with strong defocus effect caused by the main cyclotron magnetic field. Simulation study confirmed that 10 MeV proton, 65 MeV proton and 140 MeV alpha particles with 2 mm × 3 mrad could pass through the newly designed extraction system and the existing beam transport line. Beam simulation has been performed by utilizing SNOP* and OPAL** codes. * SNOP V.L. Smirnov, S.B. Vorozhtsov, Proc. of RUPAC2012 TUPPB008 325 (2012) ** The OPAL (Object Oriented Parallel Accelerator Library) Framework, Andreas Adelmann et al., PSI-PR-08-02, (2008-2018)
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPTS028
About •	paper received ※ 01 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
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TUPTS029	The New Eddy Current type Septum Magnets for Upgrading of Fast Extraction in Main Ring of J-PARC	operation, extraction, experiment, feedback	1997
	T. Shibata, K. Ishii, H. Matsumoto, T. Sugimoto KEK, Ibaraki, Japan K. Fan HUST, Wuhan, People’s Republic of China K. Hamano Nichicon (Kusatsu) Corporation, Shiga, Japan
	The J-PARC Main Ring (MR) is working on imporved beam to 750 kW by shorting the repetition period from 2.48 s to 1.3 s which we call 1Hz operation. The septum magnets for fast extraction in MR will be improved to the new septum magnets which can operate 1Hz. The new magnets will be installed to MR in 2021. In this poster we will report about the new low field septum magnet for the fast extraction. The present septum magnets are conventional type. Therefore, we have problem in durability of thin septum coil by its magnetic vibration, and large leakage field at the exit of the circulating beam duct. The new septum magnets are eddy current type. The eddy current type does not have septum coil, but has a thin septum plate. We can expect that there is no problem in durability of septum coil, and leakage field can be reduced. The output of the present power supply are pattern current which of flat top is 10 ms width, the new one is short pulse which of one is 10 us. The short pulse consists of fundamental and 3rd harmonic sin-wave pulse. We can expect that the flatness and reproducibility of flat top current can be improved. We confirmed that 1Hz operation and high accuracy of its output current and magnetic field with the new septum magnet system. We had some problem in unexpected instability of output current. In this report we also summarize the measure against the instabillity.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPTS029
About •	paper received ※ 26 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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TUPTS030	The New High Field Septum Magnets for Upgrading of Fast Extraction in Main Ring of J-PARC	operation, extraction, flattop, power-supply	2001
	T. Shibata, K. Ishii, H. Matsumoto, T. Sugimoto KEK, Ibaraki, Japan K. Fan HUST, Wuhan, People’s Republic of China
	The J-PARC Main Ring (MR) is working on imporved beam to 750 kW by shorting the repetition period from 2.48 s to 1.3 s which we call 1Hz operation. There are fout high field septum magnet along the fast extraction line in the MR, and these will be improved to the new magnets which can operate 1Hz frequency. The new high field septa will be installed in 2021. In this poster we will report about the performance of these new septum magnets. These high field septum magnets are called Septum 30(SM30), 31(SM31), 32(SM32), 33(SM33). We will replace SM30, SM31, and SM32. One reasons of cethe replacement is installation of a large-size quadrupole magnet to upsteam postion of the septa. We need to change the longitudinal length of the septa. Second is large aperture of the beam duct for reduction of beam loss by the collision of the halo of the proton beam to the duct. The new high field SM30, SM31 and SM32 have large aperture. and the material of the beam ducts for extraction line are ceramics for reduction of amount of heat generation by eddy current on the surface of the duct. The maetial of the circulating duct are titanium for reduction of radioactivation. On the other hand, the power supply will not be replaced, then the current power supplies will be used for these new septa. The new SM30, SM31, and SM32 were produced in 2015. The first test operation of SM31 were conduced with 2.48 s repein 2015, and we have meaured the magnetic field without problem. In 2018, we conduced the first 1Hz operation with SM30. The minimum repetition period of the operation was 1.16 s without any problem. We measuered magnetic fields in the gap of the pole and in the circulating beam duct. In this report we will report the detail of the results of the operation and field measurement.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPTS030
About •	paper received ※ 26 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019
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WEPMP003	Beam Dynamics and Diagnostics for the High Energy Beam Transport Line of MINERVA Project at SCK•CEN	kicker, proton, pick-up, linac	2304
	H. Kraft, L. Perrot IPN, Orsay, France
	Funding: French research agency and technologies (ANRT), through the program CIFRE (2018/0080 ) supported by THALES AVS FRANCE SAS. MYRRHA will be a research infrastructure highlighted by the first prototype of a sub-critical nuclear reactor driven by a 600 MeV particle accelerator (ADS). This project aims at exploring the transmutation of long-lived nuclear wastes. A first phase is planned to validate the reliability of a 100 MeV/4 mA Protons LINAC carrying the beam toward an ISOL facility, prefiguring the real MYRRHA demonstrator at 600 MeV. This project is called MINERVA. This paper presents the status of the beam dynamic studies for the high energy beam transport lines at 100 MeV. In agreement with the project require-ments, we describe the specificities of these beam lines for which it is needed to implement a fast kicker-septum. This system will separate the beam between two main lines: toward the beam dump or the ISOL facility. We also describe the studies on the Beam Position Monitor (BPM) selected for MYRRHA. Part of this work was sup-port by the MYRTE project of the European Union.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP003
About •	paper received ※ 24 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019
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WEPMP009	Renovation of Off-Axis Beam Injection Scheme for Next-Generation Photon Sources	injection, vacuum, kicker, photon	2318
	S. Takano, K. Fukami, C. Kondo, M. Masaki, M. Oishi, M. Shoji, K. Tamura, T. Taniuchi, T. Watanabe, K. Yanagida JASRI, Hyogo, Japan H. Akikawa, K. Sato Nihon Koshuha Co. Ltd, Yokohama, Japan K. Fukami, T. Hara, T. Inagaki, C. Kondo, M. Oishi, S. Takano, H. Tanaka, T. Watanabe RIKEN SPring-8 Center, Hyogo, Japan K. Hamato, J. Kataoka, K. Kusano, K. Ogata, Y. Saito TOKIN, Sendai, Miyagi, Japan
	Funding: Work supported by Ministry of education, culture, sports, science and technology JAPAN (MEXT). Photon sources are looking for performance upgrades by pursuing higher photon brilliance and coherence these years. The trend is pushing the lattice design to lower the beam emittance, which naturally results in the narrower dynamic aperture. One bottleneck in the upgrades is a beam injection system capable of accumulating required beam intensity and keeping top-up operations with such narrow apertures. Beam injection with a nonlinear kicker and transverse/longitudinal on-axis injections are now in the limelight. However, these techniques still need time to be put into practical use. We take an alternative approach for the SPring-8 upgrade, SPring-8-II, renovating the off-axis beam injection scheme to address the following requirements for the coming diffraction-limited storage rings (DLSRs): minimizing of both injection beam amplitude and perturbation to stored beam, and topping-up functionality. This presentation will overview the renewed off-axis beam injection scheme and report the development status of the following three key components: 1) permanent magnet based DC septum magnet, 2) in-vacuum pulse septum magnet, and 3) twin kickers driven by a single solid state pulser.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP009
About •	paper received ※ 10 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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WEPMP015	Status of the R&D for HALS Injection System	kicker, injection, storage-ring, vacuum	2335
	L. Shang, W. Liu, Y. Lu, F.L. Shang, W.B. Song, Z.B. Sun USTC/NSRL, Hefei, Anhui, People’s Republic of China
	Hefei Advanced Light Source (HALS) is a diffraction-limited synchrotron radiation source proposed by the NSRL. A comprehensive R&D program funded by the local government was initiated in the end of 2017. The program focuses on the key technologies including the injection, magnets, vacuum, mechanics, RF, etc. The formal construction of HALS is estimated to begin in 2020. This paper presents the R&D of the injection system, including the fast kicker, nanosecond pulser, NLK (non-linear kicker) and the septum magnet. Test results of the prototype fast kicker, pulsed power and the NLK are given and discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP015
About •	paper received ※ 16 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
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WEPMP032	Tracking Simulations of Shadowing Electrostatic Septum Wires by Means of Bent Crystals	simulation, extraction, optics, experiment	2395
	F.M. Velotti, M.A. Fraser, B. Goddard, V. Kain, L.S. Stoel CERN, Meyrin, Switzerland
	The Super Proton Synchrotron (SPS) slow extraction is a third integer resonant extraction and hence suffers from high losses at the electrostatic septum (ZS). This is one of the main limiting factors for the maximum number of Protons On Target (POT) deliverable from the SPS to the North Area (NA). A concept to significantly reduce the extraction losses via shadowing of the electrostatic septum wires using an upstream bent crystal has been proposed in , predicting a loss reduction of up to 50% for the prototype system installed in 2018. Following the successful experimental demonstration of the concept with beam , detailed tracking simulations have been performed to fully understand the results obtained. Further insights, such as the effective ZS width and its alignment, could be deduced by exploiting the response of the extraction loss as a function of the two degrees of freedom of the crystal (position and angle). In this paper, the beam dynamics simulations are discussed together with the implementation of the bent crystal into the simulation framework. A comparison with measurements is presented before proposals for new configurations and parameters are discussed. F.M. Velotti, et al., "Reduction of Resonant Slow Extraction Losses…", IPAC’18. ** F.M. Velotti, M.A. Fraser, et al., "Experimental SPS Slow Extraction Loss Reduction…", this conf.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP032
About •	paper received ※ 15 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
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WEPMP033	Slow Extraction Loss Reduction With Octupoles at the CERN SPS	extraction, octupole, multipole, proton	2399
	L.S. Stoel, H. Bartosik, M. Benedikt, M.A. Fraser, B. Goddard, V. Kain, F.M. Velotti CERN, Meyrin, Switzerland
	The powering of octupoles during third-integer resonant slow extraction has been studied and recently tested with beam at the CERN Super Proton Synchrotron (SPS) in order to increase the extraction efficiency and reduce the induced radioactivity of the extraction straight. The octupoles distort the particle trajectories in phase space in such a way that the extracted separatrix is folded, which decreases the particle density impinging the wires of the extraction septum at the expense of increasing the extracted beam emittance. During experimental SPS machine studies a reduction of over 40% in the specific (per extracted proton) beam loss measured at the extraction septum was demonstrated. In this paper, the prerequisite studies needed to safely but efficiently deploy the new extraction scheme in a limited time-frame are described, the experimental results are presented and an outlook is given towards the next steps to bring slow extraction with octupoles into routine operation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP033
About •	paper received ※ 14 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
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WEPMP043	Injection Studies for the Proposed Diamond-II Storage Ring	injection, booster, kicker, storage-ring	2430
	I.P.S. Martin, R. Bartolini, H. Ghasem, J.P. Kennedy, B. Singh DLS, Oxfordshire, United Kingdom
	The baseline design for the Diamond-II storage ring consists of a Modified-Hybrid 6-Bend Achromat, combining the ESRF-EBS low-emittance cell design with the DDBA mid-straight concept,. This cell design provides sufficient dynamic aperture to permit an off-axis injection scheme, provided the emittance of the injected beam is sufficiently low. In this paper we present simulations of an injection scheme using the anti-septum concept*, along with the design of an upgrade to the existing booster synchrotron. Alternate injection strategies are also discussed. ESRF Technical Design Study, ’The Orange Book’, (2014) R. Bartolini et al., PRAB 21, 050701, (2018) *C. Gough, M. Aiba, Proc. IPAC 2017, Copenhagen, Denmark, paper MOPIK104, (2017)
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP043
About •	paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
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WEPMP044	Mu2e Electrostatic Septa Volumetric Exchange of Fc-40 Dielectric in High Radiation Environments	radiation, GUI, cathode, extraction	2434
	M.L. Alvarez, A. Deshpande, K.R. Hunden, V.P. Nagaslaev, E. Pirtle Fermilab, Batavia, Illinois, USA
	Funding: * Operated by FRA, LLC under Contract No. DEAC02-07CH11359 and Grant Award No. LAB 18-1802 with the United States Department of Energy. Two electrostatic septa (ESS) are being designed for the slow extraction of 8 GeV proton beam for the Mu2e experiment at Fermilab. Special attention is given to the high voltage feedthrough (HVF), which energizes the cathode creating the bending field. The FC-40 dielectric fluid, surrounding the HV cable breaks down from radiation exposure, which reduces its insulating capabilities. The new HVF design focuses on effective replacement of the exposed fluid and eliminating the stagnant areas of low exchange rate. A preliminary test using a fully transparent prototype HVF and water was conducted to understand the volumetric exchange rate of the high radiation region. Here we discuss the results of these tests and further studies using the FC-40. malvare4@fnal.gov * vnagasl@fnal.gov
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP044
About •	paper received ※ 14 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019
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WEPMP051	Impedance Study of a New Septum Chamber of SPEAR3	impedance, simulation, vacuum, storage-ring	2447
	K. Tian, J. Langton, J.J. Sebek SLAC, Menlo Park, California, USA
	Funding: Work supported by US Department of Energy Contract DE-AC03-76SF00515. A new Septum magnet and chamber has been designed for the storage ring as a part of the accelerator improvement plan for operating a lower emittance lattice in SPEAR3. Therefore it is necessary to analyze the impedance effects on the beam from the new Septum chamber. Due to the complex design at the downstream transition of the Septum chamber, the longitudinal impedance is particular of concern. In this paper, we will present numerical simulation results for this particular component as well as the general analysis for the impedance effects of the whole chamber.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP051
About •	paper received ※ 14 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
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WEPMP052	Proposed Hadron Injection into the Future eRHIC Collider	injection, dipole, hadron, kicker	2451
	N. Tsoupas, F. Méot, C. Montag, V. Ptitsyn, D. Trbojevic, F.J. Willeke, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work Supported by the US Department of Energy. The future eRHIC collider will collide 5, 10, and 18 GeV polarized electrons with 250 GeV polarized protons, 210 GeV/u polarized 3He ions and other heavy ion species which are already produced by the RHIC accelerator. To increase the luminosity during collisions the number of circulating hadron bunches will increase to 330 and this requires a modification of the injection hadrons into the RHIC accelerator. This paper describes this injection scheme which is compatible with a design option which uses two hadron rings, one ring for accelerating the hadron beam and the other ring for storing the circulating beam to increase even further the integrated luminosity of the electron-hadron collisions. This two-hadron-rings option will be presented in the conference. tsoupas@bnl.gov * ICFA BD Newsletter No. 74 http://icfa-bd.kek.jp/
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP052
About •	paper received ※ 15 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019
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THXXPLM2	Demonstration of Loss Reduction Using a Thin Bent Crystal to Shadow an Electrostatic Septum During Resonant Slow Extraction	extraction, operation, optics, experiment	3399
	F.M. Velotti, P. Bestmann, M.E.J. Butcher, M. Calviani, M. Di Castro, M. Donzé, L.S. Esposito, M.A. Fraser, M. Garattini, S.S. Gilardoni, B. Goddard, V. Kain, J. Lendaro, A. Masi, D. Mirarchi, M. Pari, J. Prieto, S. Redaelli, R. Rossi, W. Scandale, R. Seidenbinder, P. Serrano Galvez, L.S. Stoel, C. Zamantzas, V. Zhovkovska CERN, Meyrin, Switzerland F.M. Addesa, F. Iacoangeli INFN-Roma, Roma, Italy A.G. Afonin, Y.A. Chesnokov, A.A. Durum, V.A. Maisheev, Yu.E. Sandomirskiy, A.A. Yanovich IHEP, Moscow Region, Russia J.E. Borg, M. Garattini, G. Hall, T. James, M. Pesaresi Imperial College of Science and Technology, Department of Physics, London, United Kingdom A.S. Denisov, Y. Gavrikov, Yu.M. Ivanov, M.A. Koznov, L.G. Malyarenko, V. Skorobogatov PNPI, Gatchina, Leningrad District, Russia F. Galluccio INFN-Napoli, Napoli, Italy F. Murtas INFN/LNF, Frascati, Italy
	A proof-of-principle experiment demonstrating the feasibility of using a thin, bent crystal aligned upstream of an extraction septum (ES) to increase the efficiency of the third-integer resonant slow extraction process has been carried out at the CERN Super Proton Synchrotron (SPS). With the primary aim of reducing the beam loss and induced radio-activation of the SPS, the crystal was aligned to both the beam and the septum to reduce by up to 40% the beam intensity impinging the ES and increase the intensity entering the external transfer line. In this contribution, we introduce the concept and the prototype system that was installed in 2018 before reporting in detail on the dedicated program of machine development studies carried out to characterise its performance and demonstrate operational feasibility. The performance reach and compatibility with other loss reduction techniques proposed to further increase the extraction efficiency, such as phase space folding with octupoles, is discussed in view of future high intensity operation.
	Slides THXXPLM2 [1.397 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THXXPLM2
About •	paper received ※ 15 May 2019 paper accepted ※ 28 May 2019 issue date ※ 21 June 2019
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THPRB043	Design and Simulation of Thin Eddy-Current Septum for Injection of Diffraction Limited Storage Ring	injection, simulation, HOM, storage-ring	3908
	J. Tong, M. Gu, B. Liu, Y.F. Liu, R. Wang SINAP, Shanghai, People’s Republic of China
	Funding: Work supported by the National Key Research and Development Program of China(Grant No.2016YFA0402002) Ultra-low emittance in Diffraction Limited Storage Ring (DLSR) usually has small Dynamic Aperture (DA), which makes the traditional off-axis injection inadequate. Fast kickers together with thin septum magnets or direct current lambertsons could support on-axis injection for closely-spaced bunches with small DA. Thin eddy-current septum prototype had been designed for injection with laminated silicon steel sheets as magnet core. Theoretical analysis and transient simulation had been carried out within OPERA software. Due to the minimum thickness of the septa is only 1 mm , several optimization approaches had been applied, such as shielding with strongly paramagnetic material and exciting with full cycle driving pulse, to satisfy the requirement that the leakage field is less than 0.1% with respect to the main one.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB043
About •	paper received ※ 29 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019
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THPRB080	Automatisation of the SPS ElectroStatic Septa Alignment	alignment, simulation, extraction, operation	4001
	S. Hirlaender ATI, Vienna, Austria M.A. Fraser, B. Goddard, V. Kain, J. Prieto, L.S. Stoel, F.M. Velotti CERN, Geneva, Switzerland M. Szakaly Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, Budapest, Hungary
	An electrostatic septum composed of 5 separate tanks is used to slow-extract the 400 GeV proton beam resonantly on the third integer resonance from the CERN SPS. The septa are all mounted on a single support structure that can move the ensemble coherently and, in addition, the internal anode and cathode of each tank can be moved independently. The septum is aligned to the beam by measuring and minimising the induced beam loss signals in the extraction region following an alignment procedure that is usually carried out manually at the beginning of each year. The large number of positional degrees of freedom complicates the procedure and until recently each tank was aligned one after the other semi-manually, typically requiring 8 hours. It is not uncommon that the septum has to be re-aligned later in the run taking time away from physics programme. To tackle this issue, a simplified beam dynamics and scattering simulation routine was developed to permit error studies with a large number of seeds to be carried out in a reasonable computation time. In this contribution, the simulation model will be described before the results of its exploitation to understand the efficacy of alignment procedures based on different optimization algorithms are discussed and compared to the present operational procedure. The effort culminated with the implementation of an automated alignment procedure based on a Powell optimisation algorithm that reduced the time needed to align the septum by over an order of magnitude.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB080
About •	paper received ※ 14 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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THPTS062	Alternative Proposal for FCC-hh Extraction Septa	extraction, quadrupole, vacuum, simulation	4248
	A. Sanz Ull, M.G. Atanasov, B. Balhan, J.C.C.M. Borburgh CERN, Geneva, Switzerland
	Challenging requirements are set for the FCC extraction septa magnets, notably for the magnetic field level, the septum thickness and the leak field. An alternative to the baseline FCC extraction layout with normal conducting Lambertson septa is proposed, consisting of a Superconducting Shield (SuShi) stage and a Truncated Cosine theta septa stage with the aim of reducing the necessary number of septa and installed length. The principal parameters of the septa are described and the feasibility discussed. Areas for study improvement are identified. This paper is intended for publication in the PRAB special edition.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPTS062
About •	paper received ※ 13 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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Paper

Title

Other Keywords

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MOPTS030

Characterisation and First Beam Line Tests of the Elbe Stripline Kicker

kicker, laser, neutron, simulation

918

Ch. Schneider, A. Arnold, M. Freitag, J. Hauser, P. Michel
HZDR, Dresden, Germany

The linac based CW electron accelerator ELBE operates different secondary beamlines one at a time. For the future different end stations should be served simultaneously, hence specific bunch patterns have to be kicked into different beam-lines. The variability of the bunch pattern and the frequency resp. switching time are one of the main arguments for a stripline-kicker. A design with two tapered active electrodes and two ground fenders was optimized in time and frequency domain with the software package CST. From that a design has been transferred into a construction and was manufactured. The prototype has been tested in the laboratory and installed in the ELBE beam line. The presentation summarises the recent results and the first beam line test.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPTS030

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paper received ※ 10 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

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TUPTS028

Extraction System of Upgraded AVF Cyclotron of RCNP

proton, extraction, cyclotron, injection

1993

M. Nakao, M. Fukuda, S. Hara, T. Hara, K. Hatanaka, K. Kamakura, H. Kanda, H.W. Koay, S. Morinobu, Y. Morita, K. Nagayama, T. Saito, K. Takeda, H. Tamura, Y. Yasuda, T. Yorita
RCNP, Osaka, Japan

The AVF cyclotron of RCNP have been utilized for the purposes of basic research in physics, RI production for medicine and industrial applications as well as injector of ring cyclotron. Increasing beam intensity without decreasing beam quality can make improvements in all purposes. The improvement and repair of the AVF cyclotron are being carried out currently. We designed the new LEBT, injection, acceleration and extraction systems and we report on the extraction system here. High extraction efficiency is indispensable when increasing the beam intensity since beam loss causes activation of apparatus. New extraction system consists of deflector electrodes and two gradient correctors and probes. One gradient corrector causes a horizontally focus effect on the beam and the other causes horizontally defocus effect to avoid spreading of the beam with strong defocus effect caused by the main cyclotron magnetic field. Simulation study confirmed that 10 MeV proton, 65 MeV proton and 140 MeV alpha particles with 2 mm × 3 mrad could pass through the newly designed extraction system and the existing beam transport line. Beam simulation has been performed by utilizing SNOP* and OPAL** codes.
* SNOP V.L. Smirnov, S.B. Vorozhtsov, Proc. of RUPAC2012 TUPPB008 325 (2012)
** The OPAL (Object Oriented Parallel Accelerator Library) Framework, Andreas Adelmann et al., PSI-PR-08-02, (2008-2018)

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paper received ※ 01 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

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TUPTS029

The New Eddy Current type Septum Magnets for Upgrading of Fast Extraction in Main Ring of J-PARC

operation, extraction, experiment, feedback

1997

T. Shibata, K. Ishii, H. Matsumoto, T. Sugimoto
KEK, Ibaraki, Japan
K. Fan
HUST, Wuhan, People’s Republic of China
K. Hamano
Nichicon (Kusatsu) Corporation, Shiga, Japan

The J-PARC Main Ring (MR) is working on imporved beam to 750 kW by shorting the repetition period from 2.48 s to 1.3 s which we call 1Hz operation. The septum magnets for fast extraction in MR will be improved to the new septum magnets which can operate 1Hz. The new magnets will be installed to MR in 2021. In this poster we will report about the new low field septum magnet for the fast extraction. The present septum magnets are conventional type. Therefore, we have problem in durability of thin septum coil by its magnetic vibration, and large leakage field at the exit of the circulating beam duct. The new septum magnets are eddy current type. The eddy current type does not have septum coil, but has a thin septum plate. We can expect that there is no problem in durability of septum coil, and leakage field can be reduced. The output of the present power supply are pattern current which of flat top is 10 ms width, the new one is short pulse which of one is 10 us. The short pulse consists of fundamental and 3rd harmonic sin-wave pulse. We can expect that the flatness and reproducibility of flat top current can be improved. We confirmed that 1Hz operation and high accuracy of its output current and magnetic field with the new septum magnet system. We had some problem in unexpected instability of output current. In this report we also summarize the measure against the instabillity.

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paper received ※ 26 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

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TUPTS030

The New High Field Septum Magnets for Upgrading of Fast Extraction in Main Ring of J-PARC

operation, extraction, flattop, power-supply

2001

T. Shibata, K. Ishii, H. Matsumoto, T. Sugimoto
KEK, Ibaraki, Japan
K. Fan
HUST, Wuhan, People’s Republic of China

The J-PARC Main Ring (MR) is working on imporved beam to 750 kW by shorting the repetition period from 2.48 s to 1.3 s which we call 1Hz operation. There are fout high field septum magnet along the fast extraction line in the MR, and these will be improved to the new magnets which can operate 1Hz frequency. The new high field septa will be installed in 2021. In this poster we will report about the performance of these new septum magnets. These high field septum magnets are called Septum 30(SM30), 31(SM31), 32(SM32), 33(SM33). We will replace SM30, SM31, and SM32. One reasons of cethe replacement is installation of a large-size quadrupole magnet to upsteam postion of the septa. We need to change the longitudinal length of the septa. Second is large aperture of the beam duct for reduction of beam loss by the collision of the halo of the proton beam to the duct. The new high field SM30, SM31 and SM32 have large aperture. and the material of the beam ducts for extraction line are ceramics for reduction of amount of heat generation by eddy current on the surface of the duct. The maetial of the circulating duct are titanium for reduction of radioactivation. On the other hand, the power supply will not be replaced, then the current power supplies will be used for these new septa. The new SM30, SM31, and SM32 were produced in 2015. The first test operation of SM31 were conduced with 2.48 s repein 2015, and we have meaured the magnetic field without problem. In 2018, we conduced the first 1Hz operation with SM30. The minimum repetition period of the operation was 1.16 s without any problem. We measuered magnetic fields in the gap of the pole and in the circulating beam duct. In this report we will report the detail of the results of the operation and field measurement.

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paper received ※ 26 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019

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WEPMP003

Beam Dynamics and Diagnostics for the High Energy Beam Transport Line of MINERVA Project at SCK•CEN

kicker, proton, pick-up, linac

2304

H. Kraft, L. Perrot
IPN, Orsay, France

Funding: French research agency and technologies (ANRT), through the program CIFRE (2018/0080 ) supported by THALES AVS FRANCE SAS.
MYRRHA will be a research infrastructure highlighted by the first prototype of a sub-critical nuclear reactor driven by a 600 MeV particle accelerator (ADS). This project aims at exploring the transmutation of long-lived nuclear wastes. A first phase is planned to validate the reliability of a 100 MeV/4 mA Protons LINAC carrying the beam toward an ISOL facility, prefiguring the real MYRRHA demonstrator at 600 MeV. This project is called MINERVA. This paper presents the status of the beam dynamic studies for the high energy beam transport lines at 100 MeV. In agreement with the project require-ments, we describe the specificities of these beam lines for which it is needed to implement a fast kicker-septum. This system will separate the beam between two main lines: toward the beam dump or the ISOL facility. We also describe the studies on the Beam Position Monitor (BPM) selected for MYRRHA. Part of this work was sup-port by the MYRTE project of the European Union.

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paper received ※ 24 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019

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WEPMP009

Renovation of Off-Axis Beam Injection Scheme for Next-Generation Photon Sources

injection, vacuum, kicker, photon

2318

S. Takano, K. Fukami, C. Kondo, M. Masaki, M. Oishi, M. Shoji, K. Tamura, T. Taniuchi, T. Watanabe, K. Yanagida
JASRI, Hyogo, Japan
H. Akikawa, K. Sato
Nihon Koshuha Co. Ltd, Yokohama, Japan
K. Fukami, T. Hara, T. Inagaki, C. Kondo, M. Oishi, S. Takano, H. Tanaka, T. Watanabe
RIKEN SPring-8 Center, Hyogo, Japan
K. Hamato, J. Kataoka, K. Kusano, K. Ogata, Y. Saito
TOKIN, Sendai, Miyagi, Japan

Funding: Work supported by Ministry of education, culture, sports, science and technology JAPAN (MEXT).
Photon sources are looking for performance upgrades by pursuing higher photon brilliance and coherence these years. The trend is pushing the lattice design to lower the beam emittance, which naturally results in the narrower dynamic aperture. One bottleneck in the upgrades is a beam injection system capable of accumulating required beam intensity and keeping top-up operations with such narrow apertures. Beam injection with a nonlinear kicker and transverse/longitudinal on-axis injections are now in the limelight. However, these techniques still need time to be put into practical use. We take an alternative approach for the SPring-8 upgrade, SPring-8-II, renovating the off-axis beam injection scheme to address the following requirements for the coming diffraction-limited storage rings (DLSRs): minimizing of both injection beam amplitude and perturbation to stored beam, and topping-up functionality. This presentation will overview the renewed off-axis beam injection scheme and report the development status of the following three key components: 1) permanent magnet based DC septum magnet, 2) in-vacuum pulse septum magnet, and 3) twin kickers driven by a single solid state pulser.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP009

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paper received ※ 10 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

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WEPMP015

Status of the R&D for HALS Injection System

kicker, injection, storage-ring, vacuum

2335

L. Shang, W. Liu, Y. Lu, F.L. Shang, W.B. Song, Z.B. Sun
USTC/NSRL, Hefei, Anhui, People’s Republic of China

Hefei Advanced Light Source (HALS) is a diffraction-limited synchrotron radiation source proposed by the NSRL. A comprehensive R&D program funded by the local government was initiated in the end of 2017. The program focuses on the key technologies including the injection, magnets, vacuum, mechanics, RF, etc. The formal construction of HALS is estimated to begin in 2020. This paper presents the R&D of the injection system, including the fast kicker, nanosecond pulser, NLK (non-linear kicker) and the septum magnet. Test results of the prototype fast kicker, pulsed power and the NLK are given and discussed.

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paper received ※ 16 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

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WEPMP032

Tracking Simulations of Shadowing Electrostatic Septum Wires by Means of Bent Crystals

simulation, extraction, optics, experiment

2395

F.M. Velotti, M.A. Fraser, B. Goddard, V. Kain, L.S. Stoel
CERN, Meyrin, Switzerland

The Super Proton Synchrotron (SPS) slow extraction is a third integer resonant extraction and hence suffers from high losses at the electrostatic septum (ZS). This is one of the main limiting factors for the maximum number of Protons On Target (POT) deliverable from the SPS to the North Area (NA). A concept to significantly reduce the extraction losses via shadowing of the electrostatic septum wires using an upstream bent crystal has been proposed in *, predicting a loss reduction of up to 50% for the prototype system installed in 2018. Following the successful experimental demonstration of the concept with beam **, detailed tracking simulations have been performed to fully understand the results obtained. Further insights, such as the effective ZS width and its alignment, could be deduced by exploiting the response of the extraction loss as a function of the two degrees of freedom of the crystal (position and angle). In this paper, the beam dynamics simulations are discussed together with the implementation of the bent crystal into the simulation framework. A comparison with measurements is presented before proposals for new configurations and parameters are discussed.
* F.M. Velotti, et al., "Reduction of Resonant Slow Extraction Losses…", IPAC’18.
** F.M. Velotti, M.A. Fraser, et al., "Experimental SPS Slow Extraction Loss Reduction…", this conf.

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paper received ※ 15 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

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WEPMP033

Slow Extraction Loss Reduction With Octupoles at the CERN SPS

extraction, octupole, multipole, proton

2399

L.S. Stoel, H. Bartosik, M. Benedikt, M.A. Fraser, B. Goddard, V. Kain, F.M. Velotti
CERN, Meyrin, Switzerland

The powering of octupoles during third-integer resonant slow extraction has been studied and recently tested with beam at the CERN Super Proton Synchrotron (SPS) in order to increase the extraction efficiency and reduce the induced radioactivity of the extraction straight. The octupoles distort the particle trajectories in phase space in such a way that the extracted separatrix is folded, which decreases the particle density impinging the wires of the extraction septum at the expense of increasing the extracted beam emittance. During experimental SPS machine studies a reduction of over 40% in the specific (per extracted proton) beam loss measured at the extraction septum was demonstrated. In this paper, the prerequisite studies needed to safely but efficiently deploy the new extraction scheme in a limited time-frame are described, the experimental results are presented and an outlook is given towards the next steps to bring slow extraction with octupoles into routine operation.

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP033

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paper received ※ 14 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

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WEPMP043

Injection Studies for the Proposed Diamond-II Storage Ring

injection, booster, kicker, storage-ring

2430

I.P.S. Martin, R. Bartolini, H. Ghasem, J.P. Kennedy, B. Singh
DLS, Oxfordshire, United Kingdom

The baseline design for the Diamond-II storage ring consists of a Modified-Hybrid 6-Bend Achromat, combining the ESRF-EBS low-emittance cell design with the DDBA mid-straight concept*,**. This cell design provides sufficient dynamic aperture to permit an off-axis injection scheme, provided the emittance of the injected beam is sufficiently low. In this paper we present simulations of an injection scheme using the anti-septum concept***, along with the design of an upgrade to the existing booster synchrotron. Alternate injection strategies are also discussed.
*ESRF Technical Design Study, ’The Orange Book’, (2014)
**R. Bartolini et al., PRAB 21, 050701, (2018)
***C. Gough, M. Aiba, Proc. IPAC 2017, Copenhagen, Denmark, paper MOPIK104, (2017)

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paper received ※ 15 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

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WEPMP044

Mu2e Electrostatic Septa Volumetric Exchange of Fc-40 Dielectric in High Radiation Environments

radiation, GUI, cathode, extraction

2434

M.L. Alvarez, A. Deshpande, K.R. Hunden, V.P. Nagaslaev, E. Pirtle
Fermilab, Batavia, Illinois, USA

Funding: * Operated by FRA, LLC under Contract No. DEAC02-07CH11359 and Grant Award No. LAB 18-1802 with the United States Department of Energy.
Two electrostatic septa (ESS) are being designed for the slow extraction of 8 GeV proton beam for the Mu2e experiment at Fermilab. Special attention is given to the high voltage feedthrough (HVF), which energizes the cathode creating the bending field. The FC-40 dielectric fluid, surrounding the HV cable breaks down from radiation exposure, which reduces its insulating capabilities. The new HVF design focuses on effective replacement of the exposed fluid and eliminating the stagnant areas of low exchange rate. A preliminary test using a fully transparent prototype HVF and water was conducted to understand the volumetric exchange rate of the high radiation region. Here we discuss the results of these tests and further studies using the FC-40.
** malvare4@fnal.gov
*** vnagasl@fnal.gov

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reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPMP044

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paper received ※ 14 May 2019 paper accepted ※ 23 May 2019 issue date ※ 21 June 2019

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WEPMP051

Impedance Study of a New Septum Chamber of SPEAR3

impedance, simulation, vacuum, storage-ring

2447

K. Tian, J. Langton, J.J. Sebek
SLAC, Menlo Park, California, USA

Funding: Work supported by US Department of Energy Contract DE-AC03-76SF00515.
A new Septum magnet and chamber has been designed for the storage ring as a part of the accelerator improvement plan for operating a lower emittance lattice in SPEAR3. Therefore it is necessary to analyze the impedance effects on the beam from the new Septum chamber. Due to the complex design at the downstream transition of the Septum chamber, the longitudinal impedance is particular of concern. In this paper, we will present numerical simulation results for this particular component as well as the general analysis for the impedance effects of the whole chamber.

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paper received ※ 14 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

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WEPMP052

Proposed Hadron Injection into the Future eRHIC Collider

injection, dipole, hadron, kicker

2451

N. Tsoupas, F. Méot, C. Montag, V. Ptitsyn, D. Trbojevic, F.J. Willeke, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: *Work Supported by the US Department of Energy.
The future eRHIC collider * will collide 5, 10, and 18 GeV polarized electrons with 250 GeV polarized protons, 210 GeV/u polarized 3He ions and other heavy ion species which are already produced by the RHIC accelerator. To increase the luminosity during collisions the number of circulating hadron bunches will increase to 330 and this requires a modification of the injection hadrons into the RHIC accelerator. This paper describes this injection scheme which is compatible with a design option which uses two hadron rings, one ring for accelerating the hadron beam and the other ring for storing the circulating beam to increase even further the integrated luminosity of the electron-hadron collisions. This two-hadron-rings option will be presented in the conference.
tsoupas@bnl.gov
* ICFA BD Newsletter No. 74 http://icfa-bd.kek.jp/

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paper received ※ 15 May 2019 paper accepted ※ 20 May 2019 issue date ※ 21 June 2019

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THXXPLM2

Demonstration of Loss Reduction Using a Thin Bent Crystal to Shadow an Electrostatic Septum During Resonant Slow Extraction

extraction, operation, optics, experiment

3399

F.M. Velotti, P. Bestmann, M.E.J. Butcher, M. Calviani, M. Di Castro, M. Donzé, L.S. Esposito, M.A. Fraser, M. Garattini, S.S. Gilardoni, B. Goddard, V. Kain, J. Lendaro, A. Masi, D. Mirarchi, M. Pari, J. Prieto, S. Redaelli, R. Rossi, W. Scandale, R. Seidenbinder, P. Serrano Galvez, L.S. Stoel, C. Zamantzas, V. Zhovkovska
CERN, Meyrin, Switzerland
F.M. Addesa, F. Iacoangeli
INFN-Roma, Roma, Italy
A.G. Afonin, Y.A. Chesnokov, A.A. Durum, V.A. Maisheev, Yu.E. Sandomirskiy, A.A. Yanovich
IHEP, Moscow Region, Russia
J.E. Borg, M. Garattini, G. Hall, T. James, M. Pesaresi
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
A.S. Denisov, Y. Gavrikov, Yu.M. Ivanov, M.A. Koznov, L.G. Malyarenko, V. Skorobogatov
PNPI, Gatchina, Leningrad District, Russia
F. Galluccio
INFN-Napoli, Napoli, Italy
F. Murtas
INFN/LNF, Frascati, Italy

A proof-of-principle experiment demonstrating the feasibility of using a thin, bent crystal aligned upstream of an extraction septum (ES) to increase the efficiency of the third-integer resonant slow extraction process has been carried out at the CERN Super Proton Synchrotron (SPS). With the primary aim of reducing the beam loss and induced radio-activation of the SPS, the crystal was aligned to both the beam and the septum to reduce by up to 40% the beam intensity impinging the ES and increase the intensity entering the external transfer line. In this contribution, we introduce the concept and the prototype system that was installed in 2018 before reporting in detail on the dedicated program of machine development studies carried out to characterise its performance and demonstrate operational feasibility. The performance reach and compatibility with other loss reduction techniques proposed to further increase the extraction efficiency, such as phase space folding with octupoles, is discussed in view of future high intensity operation.

Slides THXXPLM2 [1.397 MB]

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paper received ※ 15 May 2019 paper accepted ※ 28 May 2019 issue date ※ 21 June 2019

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THPRB043

Design and Simulation of Thin Eddy-Current Septum for Injection of Diffraction Limited Storage Ring

injection, simulation, HOM, storage-ring

3908

J. Tong, M. Gu, B. Liu, Y.F. Liu, R. Wang
SINAP, Shanghai, People’s Republic of China

Funding: Work supported by the National Key Research and Development Program of China(Grant No.2016YFA0402002)
Ultra-low emittance in Diffraction Limited Storage Ring (DLSR) usually has small Dynamic Aperture (DA), which makes the traditional off-axis injection inadequate. Fast kickers together with thin septum magnets or direct current lambertsons could support on-axis injection for closely-spaced bunches with small DA. Thin eddy-current septum prototype had been designed for injection with laminated silicon steel sheets as magnet core. Theoretical analysis and transient simulation had been carried out within OPERA software. Due to the minimum thickness of the septa is only 1 mm , several optimization approaches had been applied, such as shielding with strongly paramagnetic material and exciting with full cycle driving pulse, to satisfy the requirement that the leakage field is less than 0.1% with respect to the main one.

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paper received ※ 29 April 2019 paper accepted ※ 21 May 2019 issue date ※ 21 June 2019

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THPRB080

Automatisation of the SPS ElectroStatic Septa Alignment

alignment, simulation, extraction, operation

4001

S. Hirlaender
ATI, Vienna, Austria
M.A. Fraser, B. Goddard, V. Kain, J. Prieto, L.S. Stoel, F.M. Velotti
CERN, Geneva, Switzerland
M. Szakaly
Wigner Research Centre for Physics, Institute for Particle and Nuclear Physics, Budapest, Hungary

An electrostatic septum composed of 5 separate tanks is used to slow-extract the 400 GeV proton beam resonantly on the third integer resonance from the CERN SPS. The septa are all mounted on a single support structure that can move the ensemble coherently and, in addition, the internal anode and cathode of each tank can be moved independently. The septum is aligned to the beam by measuring and minimising the induced beam loss signals in the extraction region following an alignment procedure that is usually carried out manually at the beginning of each year. The large number of positional degrees of freedom complicates the procedure and until recently each tank was aligned one after the other semi-manually, typically requiring 8 hours. It is not uncommon that the septum has to be re-aligned later in the run taking time away from physics programme. To tackle this issue, a simplified beam dynamics and scattering simulation routine was developed to permit error studies with a large number of seeds to be carried out in a reasonable computation time. In this contribution, the simulation model will be described before the results of its exploitation to understand the efficacy of alignment procedures based on different optimization algorithms are discussed and compared to the present operational procedure. The effort culminated with the implementation of an automated alignment procedure based on a Powell optimisation algorithm that reduced the time needed to align the septum by over an order of magnitude.

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paper received ※ 14 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

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THPTS062

Alternative Proposal for FCC-hh Extraction Septa

extraction, quadrupole, vacuum, simulation

4248

A. Sanz Ull, M.G. Atanasov, B. Balhan, J.C.C.M. Borburgh
CERN, Geneva, Switzerland

Challenging requirements are set for the FCC extraction septa magnets, notably for the magnetic field level, the septum thickness and the leak field. An alternative to the baseline FCC extraction layout with normal conducting Lambertson septa is proposed, consisting of a Superconducting Shield (SuShi) stage and a Truncated Cosine theta septa stage with the aim of reducing the necessary number of septa and installed length. The principal parameters of the septa are described and the feasibility discussed. Areas for study improvement are identified.
This paper is intended for publication in the PRAB special edition.

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paper received ※ 13 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

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