HB2018 - List of Keywords (controls)

Paper	Title	Other Keywords	Page
MOP2WA04	Recent Results from the Wideband Feedback System Tests at the SPS and Future Plans	feedback, optics, kicker, coupling	38
	K.S.B. Li, H. Bartosik, M.S. Beck, E.R. Bjørsvik, W. Höfle, G. Kotzian, T.E. Levens, M. Schenk CERN, Geneva, Switzerland J.E. Dusatko, J.D. Fox, C.H. Rivetta SLAC, Menlo Park, California, USA M. Schenk EPFL, Lausanne, Switzerland O. Turgut Stanford University, Stanford, California, USA
	A high bandwidth transverse feedback demonstrator system has been devised within the LARP framework in collaboration with SLAC for the LHC Injectors Upgrade (LIU) Project. The initial system targeted the Super Proton Synchrotron (SPS) at CERN to combat TMCI and electron cloud instabilities induced for bunches with bunch lengths at the 100 MHz scale. It features a very fast digital signal processing system running at up to 4~GS/s and high bandwidth kickers with a frequency reach of ultimately beyond 1~GHz. In recent years, the system has gradually been extended and now includes two stripline kickers for a total power of 1~kW delivering correction signals at frequencies of currently more than 700~MHz. This talk will cover recent studies using this demonstrator system to overcome TMCI limitations in the SPS. We will conclude with future plans and also briefly mention potential applications and requirements for larger machines such as the LHC or the HL-LHC.
	Slides MOP2WA04 [19.091 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP2WA04
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUA2WC01	Discussion on SARAF-LINAC Cryomodules	cavity, cryomodule, linac, solenoid	80
	N. Pichoff CEA/IRFU, Gif-sur-Yvette, France D. Chirpaz-Cerbat, R. Cubizolles, J. Dumas, R.D. Duperrier, G. Ferrand, B. Gastineau, F. Leseigneur, C. Madec, Th. Plaisant, J. Plouin IRFU, CEA, University Paris-Saclay, Gif-sur-Yvette, France
	CEA is in charge of the design, construction, installation and commissioning at SNRC of the Linac of the SARAF project. The linac is composed of an MEBT and a Superconducting linac (SCL) integrating 4 cryomodules. Nowadays, the HWR cavities and superconducting magnets prototypes are being built. The Critical Design Review of the cryomodules has just been passed in March 2018. This paper present the status of the SARAF-LINAC cryomodules.
	Slides TUA2WC01 [14.245 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA2WC01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP1WE02	Hollow Electron-Lens Assisted Collimation and Plans for the LHC	electron, operation, collimation, collider	92
	D. Mirarchi, H. Garcia Morales, A. Mereghetti, S. Redaelli, J.F. Wagner CERN, Geneva, Switzerland W. Fischer, X. Gu BNL, Upton, Long Island, New York, USA H. Garcia Morales Royal Holloway, University of London, Surrey, United Kingdom D. Mirarchi The University of Manchester, The Photon Science Institute, Manchester, United Kingdom G. Stancari Fermilab, Batavia, Illinois, USA J.F. Wagner IAP, Frankfurt am Main, Germany
	The hollow electron lens (e-lens) is a very powerful and advanced tool for active control of diffusion speed of halo particles in hadron colliders. Thus, it can be used for a controlled depletion of beam tails and enhanced beam halo collimation. This is of particular interest in view of the upgrade of the Large Hadron Collider (LHC) at CERN, in the framework of the High-Luminosity LHC project (HL-LHC). The estimated stored energy in the tails of the HL-LHC beams is about 30 MJ, posing serious constraints on its control and safe disposal. In particular, orbit jitter can cause significant loss spikes on primary collimators, which can lead to accidental beam bump and magnet quench. Successful tests of e-lens assisted collimation have been carried out at the Tevatron collider at Fermilab and a review of the main outcomes is shown. Preliminary results of recent experiments performed at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven, put in place to explore different operational scenarios studies for the HL-LHC, are also discussed. Status and plans for the deployment of hollow electron lenses at the HL-LHC are presented.
	Slides TUP1WE02 [29.382 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP1WE02
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TUP2WE01	Injection Foil Temperature Measurements at the SNS Accelerator	radiation, vacuum, linac, target	104
	W. Blokland, C.F. Luck, A. Rakhman ORNL, Oak Ridge, Tennessee, USA N.J. Evans ORNL RAD, Oak Ridge, Tennessee, USA
	Funding: This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC0500OR22725 with the U.S. Department of Energy. The SNS uses charge exchange injection to minimize losses during the accumulation of the accelerated beam in the ring. A stripper foil implements this by removing the electrons from the high intensity H⁻ beam coming from the linac. At a beam power of 1.2 MW, the foil lasts for many weeks, sometimes months. However, given the upgrade to 2.8 MW, it is important to know the current temperature of stripper foil in order to estimate its lifetime for the new beam power and beam size. In this paper, we discuss several methods to measure the temperature of stripper foil exposed to current operating conditions of the SNS accelerator. Given the high radiation in the vicinity of the foil, the uncertainty in the foil's emissivity, and available resources, we chose a two-wavelength pyrometer that is located 40 m from the foil. The pyrometer is composed of two mirrors, a refracting telescope, and two photodiodes. We present the calibration data and the temporally resolved measurements made with this pyrometer.
	Slides TUP2WE01 [13.195 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP2WE01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUA1WD04	High Intensity Proton Stacking at Fermilab: 700 kW Running	proton, injection, survey, extraction	136
	R. Ainsworth, P. Adamson, B.C. Brown, D. Capista, K.J. Hazelwood, I. Kourbanis, D.K. Morris, M. Xiao, M.-J. Yang Fermilab, Batavia, Illinois, USA
	As part of the Nova upgrades in 2012, the Recycler was repurposed as proton stacker for the Main Injector with the aim to deliver 700 kW. Since January 2017, this design power has been run routinely. The steps taken to commission the Recycler and run at 700 kW operationally will be discussed as well as plans for future running.
	Slides TUA1WD04 [62.832 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA1WD04
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUA2WD01	FAIR Commissioning - Concepts and Strategies in View of High-Intensity Operation	operation, MMI, experiment, target	141
	R.J. Steinhagen GSI, Darmstadt, Germany
	The Facility for Anti-Proton and Ion Research (FAIR) presently under construction, extends and supersedes GSI's existing infrastructure. Its core challenges include the precise control of highest proton and uranium ion beam intensities, the required extreme high vacuum conditions, machine protection and activation issues while providing a high degree of multi-user mode of operation with facility reconfiguration on time-scales of a few times per week. Being based on best-practices at other laboratories, this contribution outlines the applicable hardware and beam commissioning strategies, as well as concepts, beam-based and other accelerator systems that are being tested at the existing facility in view of the prospective FAIR operation.
	Slides TUA2WD01 [10.735 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA2WD01
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP1WA03	Beam Instabilities After Injection to the LHC	injection, simulation, emittance, operation	163
	H. Timko, T. Argyropoulos, I. Karpov, E.N. Shaposhnikova CERN, Geneva, Switzerland
	Long-lasting phase oscillations have been observed at injection into the LHC since its first start-up with beam. These oscillations, however, were not leading to noticeable losses or blow-up in operation, and were therefore not studied in detail. In 2017, dedicated measurements with high-intensity bunches revealed that oscillations can lead to losses even slightly below the baseline intensity for the high-luminosity upgrade of the LHC. For the first time, high-resolution bunch profile acquisitions were triggered directly at injection and the formation of large-amplitude non-rigid dipole oscillations was observed on a turn-by-turn basis. First simulations can reproduce this instability via bunch filamentation that takes place after injection, depending on the mismatch between the bunch and bucket size in momentum at injection.
	Slides TUP1WA03 [2.166 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP1WA03
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO015	Progress and Plan of the Fast Protection System in the RAON Accelerator	operation, MMI, interface, machine-protect	296
	H. Jin, Y. Choi, S. Lee IBS, Daejeon, Republic of Korea
	In the RAON accelerator, beams generated by ion sources like ECR-IS or ISOL are accelerated to an energy of up to 200 MeV/u before reaching the laboratory target, and the beam power reaches up to about 400 kW at that moment. During transportation of such a beam, if beam loss occurs due to a device malfunction or a sudden change in beam condition, the accelerator can be severely damaged. Therefore, we have developed a machine protection system to protect the devices by minimizing the damage and to operate the accelerator in safe. As part of the RAON machine protection system, a FPGA-based fast protection system (FPS) that can protect devices within a few tens of microseconds after detecting the moment of beam loss has been developed since 2016. The development and test of the FPS prototype was successfully completed last year, and we are now preparing for mass production of the FPS. Here we will present the progress of the FPS development and the future plan for the FPS in the RAON accelerator.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO015
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO016	Temperature Measurement of Cryomodules	cryomodule, cavity, PLC, superconducting-cavity	299
	H. Kim, J.W. Choi, Y.W. Jo, H.C. Jung, Y. Jung, J.W. Kim, M.S. Kim, Y. Kim, M. Lee IBS, Daejeon, Republic of Korea
	A quarter-wave resonator (QWR) and a half-wave resonator (HWR) cryomodules and the control systems such as programmable logic controller (PLC) are developed. Temperature sensors such as Cernox-1050 are calibrated and applied to the cryomodules. Preparation of vertical test is introduced. QWR and HWR cryomodules are fabricated and tested by using the developed PLC control system. The PLC rack and temperature monitors are shown and the human machine interfaces (HMI) screen is shown when the HWR cryomodules is tested at 2 K.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO016
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO018	Magnetic Field Tracking at CSNS/RCS	MMI, acceleration, quadrupole, dipole	306
	S.Y. Xu, S. Fu IHEP, Beijing, People's Republic of China
	Because of the differences of magnetic saturation and eddy current effects between different magnets, magnetic field tracking errors between different magnets is larger than 2.5 % at the Rapid Cycling Synchrotron (RCS) of Chinese Spallation Neutron Source (CSNS), and the induced tune shift is larger than 0.1. So larger tune shift may lead the beam to pass through the resonance lines. To reduce the magnetic field tracking errors, a method of wave form compensation for magnets of the Rapid Cycling Synchrotron was investigated on the magnets of CSNS/RCS. The wave form compensation was applied to CSNS/RCS commissioning. By performing wave form compensation, the maximum magnetic field tracking error was reduced from 2.5 % to 0.08 %, and the maximum tune shift over the ramping process was reduced from 0.1 to 0.004.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO018
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEP2PO023	Timing Adjustment of Eight Kickers and a Method to Calibrate the Kicker Current Curves During the Beam Commissioning for CSNS	kicker, timing, extraction, MMI	312
	M.Y. Huang, D.P. Jin, L. Shen, S. Wang, S.Y. Xu, P. Zhu IHEP, Beijing, People's Republic of China
	The extraction system is a key part of the China Spallation Neutron Source (CSNS) accelerator. It consists of two kinds of magnets: eight kickers and one lambertson. During the beam commissioning, the timing adjustment of eight kickers is a very important problem. In the paper, the methods to adjust the timing of eight kickers will be studied and applied to the beam commissioning. Then, the best method to adjust the timing of eight kickers will be given and used for a long time in the future.
	Poster WEP2PO023 [1.027 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO023
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP2WB03	Influence of the Cavity Field Flatness and Effect of the Phase Reference Line Errors on the Beam Dynamics of the ESS Linac	cavity, linac, DTL, LLRF	377
	R. De Prisco, R. Zeng ESS, Lund, Sweden K. Czuba, T.P. Leśniak, R. Papis, D. Sikora, M. Żukociński Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	The particle longitudinal dynamics is affected by errors on the phase and amplitude of the electro-magnetic field in each cavity that cause emittance growth, beam degradation and losses. One of the causes of the phase error is the change of the ambient temperature in the LINAC tunnel, in the stub and in the klystron gallery that induces a phase drift of the signal travelling through the cables and radio frequency components. The field flatness error of each multiple cell cavity is caused by volume perturbation, cell to cell coupling, tuner penetration, etc.. In this paper it is studied the influences of these two types of errors on the beam dynamics and it is determined their tolerances such that the beam quality is kept within acceptable limits.
	Slides THP2WB03 [1.556 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-THP2WB03
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Paper

Title

Other Keywords

Page

MOP2WA04

Recent Results from the Wideband Feedback System Tests at the SPS and Future Plans

feedback, optics, kicker, coupling

38

K.S.B. Li, H. Bartosik, M.S. Beck, E.R. Bjørsvik, W. Höfle, G. Kotzian, T.E. Levens, M. Schenk
CERN, Geneva, Switzerland
J.E. Dusatko, J.D. Fox, C.H. Rivetta
SLAC, Menlo Park, California, USA
M. Schenk
EPFL, Lausanne, Switzerland
O. Turgut
Stanford University, Stanford, California, USA

A high bandwidth transverse feedback demonstrator system has been devised within the LARP framework in collaboration with SLAC for the LHC Injectors Upgrade (LIU) Project. The initial system targeted the Super Proton Synchrotron (SPS) at CERN to combat TMCI and electron cloud instabilities induced for bunches with bunch lengths at the 100 MHz scale. It features a very fast digital signal processing system running at up to 4~GS/s and high bandwidth kickers with a frequency reach of ultimately beyond 1~GHz. In recent years, the system has gradually been extended and now includes two stripline kickers for a total power of 1~kW delivering correction signals at frequencies of currently more than 700~MHz. This talk will cover recent studies using this demonstrator system to overcome TMCI limitations in the SPS. We will conclude with future plans and also briefly mention potential applications and requirements for larger machines such as the LHC or the HL-LHC.

Slides MOP2WA04 [19.091 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-MOP2WA04

Export •

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

TUA2WC01

Discussion on SARAF-LINAC Cryomodules

cavity, cryomodule, linac, solenoid

80

N. Pichoff
CEA/IRFU, Gif-sur-Yvette, France
D. Chirpaz-Cerbat, R. Cubizolles, J. Dumas, R.D. Duperrier, G. Ferrand, B. Gastineau, F. Leseigneur, C. Madec, Th. Plaisant, J. Plouin
IRFU, CEA, University Paris-Saclay, Gif-sur-Yvette, France

CEA is in charge of the design, construction, installation and commissioning at SNRC of the Linac of the SARAF project. The linac is composed of an MEBT and a Superconducting linac (SCL) integrating 4 cryomodules. Nowadays, the HWR cavities and superconducting magnets prototypes are being built. The Critical Design Review of the cryomodules has just been passed in March 2018. This paper present the status of the SARAF-LINAC cryomodules.

Slides TUA2WC01 [14.245 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA2WC01

Export •

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

TUP1WE02

Hollow Electron-Lens Assisted Collimation and Plans for the LHC

electron, operation, collimation, collider

92

D. Mirarchi, H. Garcia Morales, A. Mereghetti, S. Redaelli, J.F. Wagner
CERN, Geneva, Switzerland
W. Fischer, X. Gu
BNL, Upton, Long Island, New York, USA
H. Garcia Morales
Royal Holloway, University of London, Surrey, United Kingdom
D. Mirarchi
The University of Manchester, The Photon Science Institute, Manchester, United Kingdom
G. Stancari
Fermilab, Batavia, Illinois, USA
J.F. Wagner
IAP, Frankfurt am Main, Germany

The hollow electron lens (e-lens) is a very powerful and advanced tool for active control of diffusion speed of halo particles in hadron colliders. Thus, it can be used for a controlled depletion of beam tails and enhanced beam halo collimation. This is of particular interest in view of the upgrade of the Large Hadron Collider (LHC) at CERN, in the framework of the High-Luminosity LHC project (HL-LHC). The estimated stored energy in the tails of the HL-LHC beams is about 30 MJ, posing serious constraints on its control and safe disposal. In particular, orbit jitter can cause significant loss spikes on primary collimators, which can lead to accidental beam bump and magnet quench. Successful tests of e-lens assisted collimation have been carried out at the Tevatron collider at Fermilab and a review of the main outcomes is shown. Preliminary results of recent experiments performed at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven, put in place to explore different operational scenarios studies for the HL-LHC, are also discussed. Status and plans for the deployment of hollow electron lenses at the HL-LHC are presented.

Slides TUP1WE02 [29.382 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP1WE02

Export •

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TUP2WE01

Injection Foil Temperature Measurements at the SNS Accelerator

radiation, vacuum, linac, target

104

W. Blokland, C.F. Luck, A. Rakhman
ORNL, Oak Ridge, Tennessee, USA
N.J. Evans
ORNL RAD, Oak Ridge, Tennessee, USA

Funding: This manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC0500OR22725 with the U.S. Department of Energy.
The SNS uses charge exchange injection to minimize losses during the accumulation of the accelerated beam in the ring. A stripper foil implements this by removing the electrons from the high intensity H⁻ beam coming from the linac. At a beam power of 1.2 MW, the foil lasts for many weeks, sometimes months. However, given the upgrade to 2.8 MW, it is important to know the current temperature of stripper foil in order to estimate its lifetime for the new beam power and beam size. In this paper, we discuss several methods to measure the temperature of stripper foil exposed to current operating conditions of the SNS accelerator. Given the high radiation in the vicinity of the foil, the uncertainty in the foil's emissivity, and available resources, we chose a two-wavelength pyrometer that is located 40 m from the foil. The pyrometer is composed of two mirrors, a refracting telescope, and two photodiodes. We present the calibration data and the temporally resolved measurements made with this pyrometer.

Slides TUP2WE01 [13.195 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP2WE01

Export •

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

TUA1WD04

High Intensity Proton Stacking at Fermilab: 700 kW Running

proton, injection, survey, extraction

136

R. Ainsworth, P. Adamson, B.C. Brown, D. Capista, K.J. Hazelwood, I. Kourbanis, D.K. Morris, M. Xiao, M.-J. Yang
Fermilab, Batavia, Illinois, USA

As part of the Nova upgrades in 2012, the Recycler was repurposed as proton stacker for the Main Injector with the aim to deliver 700 kW. Since January 2017, this design power has been run routinely. The steps taken to commission the Recycler and run at 700 kW operationally will be discussed as well as plans for future running.

Slides TUA1WD04 [62.832 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA1WD04

Export •

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

TUA2WD01

FAIR Commissioning - Concepts and Strategies in View of High-Intensity Operation

operation, MMI, experiment, target

141

R.J. Steinhagen
GSI, Darmstadt, Germany

The Facility for Anti-Proton and Ion Research (FAIR) presently under construction, extends and supersedes GSI's existing infrastructure. Its core challenges include the precise control of highest proton and uranium ion beam intensities, the required extreme high vacuum conditions, machine protection and activation issues while providing a high degree of multi-user mode of operation with facility reconfiguration on time-scales of a few times per week. Being based on best-practices at other laboratories, this contribution outlines the applicable hardware and beam commissioning strategies, as well as concepts, beam-based and other accelerator systems that are being tested at the existing facility in view of the prospective FAIR operation.

Slides TUA2WD01 [10.735 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUA2WD01

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TUP1WA03

Beam Instabilities After Injection to the LHC

injection, simulation, emittance, operation

163

H. Timko, T. Argyropoulos, I. Karpov, E.N. Shaposhnikova
CERN, Geneva, Switzerland

Long-lasting phase oscillations have been observed at injection into the LHC since its first start-up with beam. These oscillations, however, were not leading to noticeable losses or blow-up in operation, and were therefore not studied in detail. In 2017, dedicated measurements with high-intensity bunches revealed that oscillations can lead to losses even slightly below the baseline intensity for the high-luminosity upgrade of the LHC. For the first time, high-resolution bunch profile acquisitions were triggered directly at injection and the formation of large-amplitude non-rigid dipole oscillations was observed on a turn-by-turn basis. First simulations can reproduce this instability via bunch filamentation that takes place after injection, depending on the mismatch between the bunch and bucket size in momentum at injection.

Slides TUP1WA03 [2.166 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-TUP1WA03

Export •

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

WEP2PO015

Progress and Plan of the Fast Protection System in the RAON Accelerator

operation, MMI, interface, machine-protect

296

H. Jin, Y. Choi, S. Lee
IBS, Daejeon, Republic of Korea

In the RAON accelerator, beams generated by ion sources like ECR-IS or ISOL are accelerated to an energy of up to 200 MeV/u before reaching the laboratory target, and the beam power reaches up to about 400 kW at that moment. During transportation of such a beam, if beam loss occurs due to a device malfunction or a sudden change in beam condition, the accelerator can be severely damaged. Therefore, we have developed a machine protection system to protect the devices by minimizing the damage and to operate the accelerator in safe. As part of the RAON machine protection system, a FPGA-based fast protection system (FPS) that can protect devices within a few tens of microseconds after detecting the moment of beam loss has been developed since 2016. The development and test of the FPS prototype was successfully completed last year, and we are now preparing for mass production of the FPS. Here we will present the progress of the FPS development and the future plan for the FPS in the RAON accelerator.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO015

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

WEP2PO016

Temperature Measurement of Cryomodules

cryomodule, cavity, PLC, superconducting-cavity

299

H. Kim, J.W. Choi, Y.W. Jo, H.C. Jung, Y. Jung, J.W. Kim, M.S. Kim, Y. Kim, M. Lee
IBS, Daejeon, Republic of Korea

A quarter-wave resonator (QWR) and a half-wave resonator (HWR) cryomodules and the control systems such as programmable logic controller (PLC) are developed. Temperature sensors such as Cernox-1050 are calibrated and applied to the cryomodules. Preparation of vertical test is introduced. QWR and HWR cryomodules are fabricated and tested by using the developed PLC control system. The PLC rack and temperature monitors are shown and the human machine interfaces (HMI) screen is shown when the HWR cryomodules is tested at 2 K.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO016

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WEP2PO018

Magnetic Field Tracking at CSNS/RCS

MMI, acceleration, quadrupole, dipole

306

S.Y. Xu, S. Fu
IHEP, Beijing, People's Republic of China

Because of the differences of magnetic saturation and eddy current effects between different magnets, magnetic field tracking errors between different magnets is larger than 2.5 % at the Rapid Cycling Synchrotron (RCS) of Chinese Spallation Neutron Source (CSNS), and the induced tune shift is larger than 0.1. So larger tune shift may lead the beam to pass through the resonance lines. To reduce the magnetic field tracking errors, a method of wave form compensation for magnets of the Rapid Cycling Synchrotron was investigated on the magnets of CSNS/RCS. The wave form compensation was applied to CSNS/RCS commissioning. By performing wave form compensation, the maximum magnetic field tracking error was reduced from 2.5 % to 0.08 %, and the maximum tune shift over the ramping process was reduced from 0.1 to 0.004.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO018

Export •

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

WEP2PO023

Timing Adjustment of Eight Kickers and a Method to Calibrate the Kicker Current Curves During the Beam Commissioning for CSNS

kicker, timing, extraction, MMI

312

M.Y. Huang, D.P. Jin, L. Shen, S. Wang, S.Y. Xu, P. Zhu
IHEP, Beijing, People's Republic of China

The extraction system is a key part of the China Spallation Neutron Source (CSNS) accelerator. It consists of two kinds of magnets: eight kickers and one lambertson. During the beam commissioning, the timing adjustment of eight kickers is a very important problem. In the paper, the methods to adjust the timing of eight kickers will be studied and applied to the beam commissioning. Then, the best method to adjust the timing of eight kickers will be given and used for a long time in the future.

Poster WEP2PO023 [1.027 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-WEP2PO023

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THP2WB03

Influence of the Cavity Field Flatness and Effect of the Phase Reference Line Errors on the Beam Dynamics of the ESS Linac

cavity, linac, DTL, LLRF

377

R. De Prisco, R. Zeng
ESS, Lund, Sweden
K. Czuba, T.P. Leśniak, R. Papis, D. Sikora, M. Żukociński
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

The particle longitudinal dynamics is affected by errors on the phase and amplitude of the electro-magnetic field in each cavity that cause emittance growth, beam degradation and losses. One of the causes of the phase error is the change of the ambient temperature in the LINAC tunnel, in the stub and in the klystron gallery that induces a phase drift of the signal travelling through the cables and radio frequency components. The field flatness error of each multiple cell cavity is caused by volume perturbation, cell to cell coupling, tuner penetration, etc.. In this paper it is studied the influences of these two types of errors on the beam dynamics and it is determined their tolerances such that the beam quality is kept within acceptable limits.

Slides THP2WB03 [1.556 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-HB2018-THP2WB03

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