IBIC2018 - Classification: 8. Feedback and beam stability

Paper	Title	Page
TUOC02	APS Upgrade Integrated Beam Stability Experiments in the APS Storage Ring
	J. Carwardine, N.D. Arnold, R.W. Blake, A.R. Brill, H. Bui, G. Decker, L. Emery, T. Fors, P.S. Kallakuri, R.T. Keane, R.M. Lill, D.R. Paskvan, A.F. Pietryla, N. Sereno, H. Shang, S. Veseli, J. Wang, S. Xu, B.X. Yang ANL, Argonne, Illinois, USA
	Funding: The submitted manuscript has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (Argonne) under U.S.Department of Energy Office of Science Contract No. DE-AC02-06CH11357. An ultra-stable orbit will be essential to take advantage of the beam properties of the multi-bend achromat lattice of the APS Upgrade. Transverse beam dimensions are an order of magnitude smaller than for the present APS (14.7 microns x 2.8 microns in flat-beam mode), and consequently orbit stability tolerances are very challenging. The APS upgrade fast orbit feedback system uses a similar architecture to the present orbit feedback system, but while the present system corrects the orbit at 1.6 kHz using 160 bpms and 38 fast correctors per plane, design specifications for APS Upgrade call for orbit correction at 22kHz using 570 rf bpms and 90 photon bpms along with 160 fast correctors per plane. A major focus of the integrated beam stability R&D has been development and test of a prototype fast orbit feedback system using two sectors of the present APS storage ring for demonstration and validation of design parameters. Hardware/firmware implementation is discussed, and we present results from the R&D program covering both orbit correction and feedback control domains, including a novel algorithm that combines orbit correction for both slow and fast correctors down to DC.
	Slides TUOC02 [9.767 MB]
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TUPC09	Initial Results from the LHC Multi-Band Instability Monitor	314
	T.E. Levens, T. Lefèvre, D. Valuch CERN, Meyrin, Switzerland
	Intra-bunch transverse instabilities are routinely measured in the LHC using a "Head-Tail Monitor" based on sampling a wide-band BPM with a high-speed digitiser. However, these measurements are limited by the dynamic range and short record length possible with typical commercial oscilloscopes. This paper will present the initial results from the LHC Multi-Band Instability Monitor, a new technique developed to provide information on the beam stability with a high dynamic range using frequency domain analysis of the transverse beam spectrum.
	Poster TUPC09 [17.388 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC09
About •	paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
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TUPC10	The Design of Scanning Control System for Proton Therapy Facility at CIAE	319
	L.C. Cao, T. Ge, F.P. Guan, S.G. Hou, X.T. Lu, Y. Wang, L.P. Wen CIAE, Beijing, People’s Republic of China
	A new proton therapy facility is being construted at CIAE. As a part of whole control system, the scanning control system is designed to scan the beam for the access of required tumor therapy field. The origin data plan comes from treatment control system. Two set of dipole magnet is driven for changing the beam path. Meanwhile, interfaces between scanning system and other systems is built for beam control and safe considering. In order to acquire high precise feedback control, the beam position and dose monitor ionization chambers will be constructed in the nozzle. Once accident occurs, the scanning system should be able to response instantly to cut off beam and inform safe interlock system simultaneously. The response time of scanning system is at tens of microsecond level, so the scanning controller, feedback controller and the monitor electronics is built in fast mode. Detailed description will be presented in this paper.
	Poster TUPC10 [0.794 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC10
About •	paper received ※ 30 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019
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TUPC11	Design of an Ultrafast Stripline Kicker for Bunch-by-Bunch Feedback	322
	J. Wang, P. Li, D. Wu, D.X. Xiao, L.G. Yan CAEP/IAE, Mianyang, Sichuan, People’s Republic of China
	Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190) The CAEP THz Free Electron Laser (CTFEL) will have a fast transverse bunch-by-bunch feedback system on its test beamline, which is used to correct the beam position differences of individual bunches with interval of about 2 ns. In this paper, we are proposing an ultrafast wideband stripline kicker, which is able to provide a kick to the bunch in a 2 ns time window. The structure design and simulation results of this kicker are also discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC11
About •	paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
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TUPC12	Beam Transverse Quadrupole Oscillation Measurement in the Injection Stage for the HLS-II Storage Ring	325
	F.F. Wu, F.L. Gao, L.T. Huang, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, J.H. Wei, T.Y. Zhou USTC/NSRL, Hefei, Anhui, People’s Republic of China
	Funding: Supported by the National Science Foundation of China (Grant No. 11705203, 11575181, 11605202) and the National Key Research and Development Program of China(No. 2016YFA0402000) Beam transverse quadrupole oscillation can be excited in the injection stage if injected beam parameters(twiss parameters or dispersion) are not matched with the parameters in the injection point of the storage ring. In order to measure the beam transverse quadrupole oscillation in the injection stage for the HLS-II storage ring, some axially symmetric stripline BPMs were designed. Transverse quadrupole component for these BPMs was simulated and off-line calibrated. Beam transverse quadrupole oscillation has been measured when beam was injected into the HLS-II electron storage ring. The spectrum of the transverse quadrupole component showed that beam transverse quadrupole oscillation is very obvious in the injection stage and this oscillation isn’t the second harmonic of beam betatron oscillation. The relationship between transverse quadrupole oscillation and beam current was also analyzed and the result shows that the relationship is not linear.
	Poster TUPC12 [0.467 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC12
About •	paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019
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TUPC13	Early Commissioning of the Luminosity Dither Feedback for SuperKEKB	328
	M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara KEK, Ibaraki, Japan P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang LAL, Orsay, France D.G. Brown, A.S. Fisher, M.K. Sullivan SLAC, Menlo Park, California, USA D. El Khechen CERN, Geneva, Switzerland U. Wienands ANL, Argonne, Illinois, USA
	SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13
About •	paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

TUOC02

APS Upgrade Integrated Beam Stability Experiments in the APS Storage Ring

J. Carwardine, N.D. Arnold, R.W. Blake, A.R. Brill, H. Bui, G. Decker, L. Emery, T. Fors, P.S. Kallakuri, R.T. Keane, R.M. Lill, D.R. Paskvan, A.F. Pietryla, N. Sereno, H. Shang, S. Veseli, J. Wang, S. Xu, B.X. Yang
ANL, Argonne, Illinois, USA

Funding: The submitted manuscript has been created by UChicago Argonne, LLC, Operator of Argonne National Laboratory (Argonne) under U.S.Department of Energy Office of Science Contract No. DE-AC02-06CH11357.
An ultra-stable orbit will be essential to take advantage of the beam properties of the multi-bend achromat lattice of the APS Upgrade. Transverse beam dimensions are an order of magnitude smaller than for the present APS (14.7 microns x 2.8 microns in flat-beam mode), and consequently orbit stability tolerances are very challenging. The APS upgrade fast orbit feedback system uses a similar architecture to the present orbit feedback system, but while the present system corrects the orbit at 1.6 kHz using 160 bpms and 38 fast correctors per plane, design specifications for APS Upgrade call for orbit correction at 22kHz using 570 rf bpms and 90 photon bpms along with 160 fast correctors per plane. A major focus of the integrated beam stability R&D has been development and test of a prototype fast orbit feedback system using two sectors of the present APS storage ring for demonstration and validation of design parameters. Hardware/firmware implementation is discussed, and we present results from the R&D program covering both orbit correction and feedback control domains, including a novel algorithm that combines orbit correction for both slow and fast correctors down to DC.

Slides TUOC02 [9.767 MB]

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TUPC09

Initial Results from the LHC Multi-Band Instability Monitor

314

T.E. Levens, T. Lefèvre, D. Valuch
CERN, Meyrin, Switzerland

Intra-bunch transverse instabilities are routinely measured in the LHC using a "Head-Tail Monitor" based on sampling a wide-band BPM with a high-speed digitiser. However, these measurements are limited by the dynamic range and short record length possible with typical commercial oscilloscopes. This paper will present the initial results from the LHC Multi-Band Instability Monitor, a new technique developed to provide information on the beam stability with a high dynamic range using frequency domain analysis of the transverse beam spectrum.

Poster TUPC09 [17.388 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC09

About •

paper received ※ 05 September 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC10

The Design of Scanning Control System for Proton Therapy Facility at CIAE

319

L.C. Cao, T. Ge, F.P. Guan, S.G. Hou, X.T. Lu, Y. Wang, L.P. Wen
CIAE, Beijing, People’s Republic of China

A new proton therapy facility is being construted at CIAE. As a part of whole control system, the scanning control system is designed to scan the beam for the access of required tumor therapy field. The origin data plan comes from treatment control system. Two set of dipole magnet is driven for changing the beam path. Meanwhile, interfaces between scanning system and other systems is built for beam control and safe considering. In order to acquire high precise feedback control, the beam position and dose monitor ionization chambers will be constructed in the nozzle. Once accident occurs, the scanning system should be able to response instantly to cut off beam and inform safe interlock system simultaneously. The response time of scanning system is at tens of microsecond level, so the scanning controller, feedback controller and the monitor electronics is built in fast mode. Detailed description will be presented in this paper.

Poster TUPC10 [0.794 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC10

About •

paper received ※ 30 August 2018 paper accepted ※ 13 September 2018 issue date ※ 29 January 2019

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

TUPC11

Design of an Ultrafast Stripline Kicker for Bunch-by-Bunch Feedback

322

J. Wang, P. Li, D. Wu, D.X. Xiao, L.G. Yan
CAEP/IAE, Mianyang, Sichuan, People’s Republic of China

Funding: Work supported by China National Key Scientific Instrument and Equipment Development Project (2011YQ130018), National Natural Science Foundation of China (11475159, 11505173, 11575264 and 11605190)
The CAEP THz Free Electron Laser (CTFEL) will have a fast transverse bunch-by-bunch feedback system on its test beamline, which is used to correct the beam position differences of individual bunches with interval of about 2 ns. In this paper, we are proposing an ultrafast wideband stripline kicker, which is able to provide a kick to the bunch in a 2 ns time window. The structure design and simulation results of this kicker are also discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC11

About •

paper received ※ 07 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

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

TUPC12

Beam Transverse Quadrupole Oscillation Measurement in the Injection Stage for the HLS-II Storage Ring

325

F.F. Wu, F.L. Gao, L.T. Huang, X.Y. Liu, P. Lu, B.G. Sun, J.G. Wang, J.H. Wei, T.Y. Zhou
USTC/NSRL, Hefei, Anhui, People’s Republic of China

Funding: Supported by the National Science Foundation of China (Grant No. 11705203, 11575181, 11605202) and the National Key Research and Development Program of China(No. 2016YFA0402000)
Beam transverse quadrupole oscillation can be excited in the injection stage if injected beam parameters(twiss parameters or dispersion) are not matched with the parameters in the injection point of the storage ring. In order to measure the beam transverse quadrupole oscillation in the injection stage for the HLS-II storage ring, some axially symmetric stripline BPMs were designed. Transverse quadrupole component for these BPMs was simulated and off-line calibrated. Beam transverse quadrupole oscillation has been measured when beam was injected into the HLS-II electron storage ring. The spectrum of the transverse quadrupole component showed that beam transverse quadrupole oscillation is very obvious in the injection stage and this oscillation isn’t the second harmonic of beam betatron oscillation. The relationship between transverse quadrupole oscillation and beam current was also analyzed and the result shows that the relationship is not linear.

Poster TUPC12 [0.467 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC12

About •

paper received ※ 06 September 2018 paper accepted ※ 12 September 2018 issue date ※ 29 January 2019

Export •

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

TUPC13

Early Commissioning of the Luminosity Dither Feedback for SuperKEKB

328

M. Masuzawa, Y. Funakoshi, T. Kawamoto, S. Nakamura, T. Oki, M. Tobiyama, S. Uehara
KEK, Ibaraki, Japan
P. Bambade, S. Di Carlo, D. Jehanno, C.G. Pang
LAL, Orsay, France
D.G. Brown, A.S. Fisher, M.K. Sullivan
SLAC, Menlo Park, California, USA
D. El Khechen
CERN, Geneva, Switzerland
U. Wienands
ANL, Argonne, Illinois, USA

SuperKEKB is an electron-positron collider, which aims to achieve a peak luminosity of 8×10³⁵ cm^-2 s⁻¹ using what is known as the "nano-beam" scheme. This paper reports on the commissioning and performance of a luminosity dither feedback. The system, based on one previously used at SLAC for PEP-II, is employed for collision orbit feedback in the horizontal plane. Twelve air-core Helmholtz coils drive the positron beam sinusoidally at a frequency near 80 Hz, forming a closed bump at the interaction point. A lock-in amplifier detects the amplitude and phase of the corresponding frequency component of the luminosity signal. When the beams are aligned for peak luminosity, the magnitude of the luminosity component at the dithering frequency becomes zero. The magnitude grows as the beams are offset, and the phase shifts by 180 degrees when the direction of the necessary correction reverses. The hardware and algorithm were tested during SuperKEKB Phase II run. The electron beam orbit was successfully adjusted to minimize the amplitude of the dither frequency component of the luminosity signal, and the optimal condition was maintained by continuously adjusting the electron beam orbit.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2018-TUPC13

About •

paper received ※ 09 September 2018 paper accepted ※ 10 September 2018 issue date ※ 29 January 2019

Export •

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