DIPAC2011 - List of Keywords (damping)

Paper	Title	Other Keywords	Page
MOPD11	High Resolution BPM Upgrade for the ATF Damping Ring at KEK	closed-orbit, injection, controls, diagnostics	59
	N. Eddy, C.I. Briegel, B.J. Fellenz, E. Gianfelice-Wendt, P.S. Prieto, R. Rechenmacher, A. Semenov, D.C. Voy, M. Wendt, D.H. Zhang Fermilab, Batavia, USA N. Terunuma, J. Urakawa KEK, Ibaraki, Japan
	Funding: Work is supported by the joint high energy physics research program of Japan-USA, and by FNAL, operated by Fermi Research Alliance LLC under contract #DE-AC02-07CH11359 with the US Dept. of Energy. A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital down-conversion techniques, digital signal processing, and also implements a new automatic gain error correction schema. The technical concept and realization as well as results of beam studies are presented.

MOPD71	Using the Transverse Digital Damper as a Real-time Tune Monitor for the Booster Synchrotron at Fermilab	booster, kicker, controls, synchrotron	209
	N. Eddy, O. Lysenko Fermilab, Batavia, USA
	The Fermilab Booster is a fast ramping (15Hz) synchrotron which accelerates protons from 400MeV to 8GeV. During commissioning of a transverse digital damper system, it was shown that the damper could provide a measurement of the the machine tune throughout the cycle by exciting just 1 of the 84 bunches with minimal impact on the machine operation. The algorithms used to make the measurement have been incorporated into the damper FPGA firmware allowing for real-time tune monitoring of all Booster cycles. Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.

MOPD74	The New Fast Orbit Correction System of the ESRF Storage Ring	storage-ring, power-supply, feedback, insertion	215
	E. Plouviez, F. Epaud, J.M. Koch, K.B. Scheidt ESRF, Grenoble, France
	The ESRF is upgrading the orbit correction system of its storage ring. The goal of this upgrade is to damp the effect on the orbit stability of the insertion devices during the changes of their settings, as well as the effect of the environmental vibrations and AC main power spurious fields; in order to achieve this goal we aim at a correction bandwith of 200Hz. The final system will use the data of 224 BPMs already equipped with Libera brilliance electronics. The correction will be applied by a set of 96 correctors implemented in the auxillary legs of the sextupolar magnets, driven by newly designed fast power supplies . The power supplies are controlled using a set of 8 FPGA boards connected to the power supplies inputs with serial links; these FPGA will also compute the correctors currents using the BPMs data. All the correctors and BPMs are now installed and interconnected and we have already performed orbit correction tests over 2 of the 32 cells of our storage ring using one single FPGA board controlling 6 correctors. These tests have allowed us to evaluate the final performance of the system. This paper presents this new system and the results of these tests.

MOPD79	An FPGA-based Turn-by-Turn Beam Position Monitoring System for Studying Multiple Bunch Beams in the ATF Damping Ring	injection, extraction, feedback, synchrotron	230
	G.B. Christian, D.R. Bett, B. Constance, M.R. Davis JAI, Oxford, United Kingdom R. Apsimon, P. Burrows, A. Gerbershagen, C. Perry Oxford University, Physics Department, Oxford, Oxon, United Kingdom J. Resta-López IFIC, Valencia, Spain
	Instabilities associated with beam-size blow-up have previously been observed with multi-bunch beam in the damping ring (DR) of the KEK Accelerator Test Facility (ATF). A system has been developed to monitor such instabilities, utilising an ATF stripline beam position monitor (BPM) in the DR, and BPM processor hardware designed for the FONT upstream feedback system in the ATF extraction line. The system is designed to record the horizontal and/or vertical positions of up to three bunches in the DR in single-bunch multi-train mode or the head bunch of up to three trains in multi-bunch mode, with a bunch spacing of 5.6 ns. The FPGA firmware and data acquisition software were modified to record turn-by-turn data for up to six channels and 1–3 bunches in the DR. The maximum memory configuration on the FPGA allows 131071 bunch-turn-channels of data to be recorded from a particular machine pulse, and the system has the capability to select only certain turns at a regular interval in which to record data, in order to zoom out and cover the entire period of the damping cycle at the ATF. An overview of the system and initial results will be presented.

TUPD13	CLIC Drive Beam Position Monitor	electron, linac, luminosity, coupling	326
	S.R. Smith, A. Cappelletti, D. Gudkov, L. Søby, I. Syratchev CERN, Geneva, Switzerland S.R. Smith SLAC, Menlo Park, California, USA
	Funding: Work supported by Department of Energy contract DE-AC02-76SF00515 CLIC, an electron-positron linear collider proposed to probe the TeV energy scale, is based on a two-beam scheme where RF power to accelerate a high energy luminosity beam is extracted from a high current drive beam. The drive beam is efficiently generated in a long train at modest frequency and current then compressed in length and multiplied in frequency via bunch interleaving. The drive beam decelerator requires >40000 quadrupoles, each holding a beam position monitor (BPM). Though resolution requirements are modest (2 microns) these BPMs face several challenges. They must be compact and inexpensive. They must operate below waveguide cutoff to insure locality of position signals, ruling out processing at the natural 12 GHz bunch spacing frequency. Wakefields must be kept low. We find compact conventional stripline BPM with signals processed below 40 MHz can meet requirements. Choices of mechanical design, operating frequency, bandwidth, calibration, and processing algorithm are presented. Calculations of wakes and trapped modes and damping are discussed.

TUPD56	High Resolution SR Profile Monitor at ATF2 Extraction Line	extraction, emittance, background, controls	434
	T. Naito, T.M. Mitsuhashi KEK, Ibaraki, Japan
	The profile monitor using visible light of the SR at ATF2 extraction line has been developed. KEK-ATF is a facility to produce extremely low emittance beam for the linear collider. The emittance in the damping ring is ex=1x10^-9 m and ey=1x10{-11} m, respectively. The ATF2 extraction line is a transport line to study the Final focus system for the linear collider. The designed beam size at the profile monitor is 230 μm in horizontal and 13 μm in vertical. We used a wide aperture optical system to reduce the Rayleigh limit of the optical system. The performance of the monitor is reported.

Paper

Title

Other Keywords

Page

MOPD11

High Resolution BPM Upgrade for the ATF Damping Ring at KEK

closed-orbit, injection, controls, diagnostics

59

N. Eddy, C.I. Briegel, B.J. Fellenz, E. Gianfelice-Wendt, P.S. Prieto, R. Rechenmacher, A. Semenov, D.C. Voy, M. Wendt, D.H. Zhang
Fermilab, Batavia, USA
N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan

Funding: Work is supported by the joint high energy physics research program of Japan-USA, and by FNAL, operated by Fermi Research Alliance LLC under contract #DE-AC02-07CH11359 with the US Dept. of Energy.
A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and digital down-conversion techniques, digital signal processing, and also implements a new automatic gain error correction schema. The technical concept and realization as well as results of beam studies are presented.

MOPD71

Using the Transverse Digital Damper as a Real-time Tune Monitor for the Booster Synchrotron at Fermilab

booster, kicker, controls, synchrotron

209

N. Eddy, O. Lysenko
Fermilab, Batavia, USA

The Fermilab Booster is a fast ramping (15Hz) synchrotron which accelerates protons from 400MeV to 8GeV. During commissioning of a transverse digital damper system, it was shown that the damper could provide a measurement of the the machine tune throughout the cycle by exciting just 1 of the 84 bunches with minimal impact on the machine operation. The algorithms used to make the measurement have been incorporated into the damper FPGA firmware allowing for real-time tune monitoring of all Booster cycles.
Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.

MOPD74

The New Fast Orbit Correction System of the ESRF Storage Ring

storage-ring, power-supply, feedback, insertion

215

E. Plouviez, F. Epaud, J.M. Koch, K.B. Scheidt
ESRF, Grenoble, France

The ESRF is upgrading the orbit correction system of its storage ring. The goal of this upgrade is to damp the effect on the orbit stability of the insertion devices during the changes of their settings, as well as the effect of the environmental vibrations and AC main power spurious fields; in order to achieve this goal we aim at a correction bandwith of 200Hz. The final system will use the data of 224 BPMs already equipped with Libera brilliance electronics. The correction will be applied by a set of 96 correctors implemented in the auxillary legs of the sextupolar magnets, driven by newly designed fast power supplies . The power supplies are controlled using a set of 8 FPGA boards connected to the power supplies inputs with serial links; these FPGA will also compute the correctors currents using the BPMs data. All the correctors and BPMs are now installed and interconnected and we have already performed orbit correction tests over 2 of the 32 cells of our storage ring using one single FPGA board controlling 6 correctors. These tests have allowed us to evaluate the final performance of the system. This paper presents this new system and the results of these tests.

MOPD79

An FPGA-based Turn-by-Turn Beam Position Monitoring System for Studying Multiple Bunch Beams in the ATF Damping Ring

injection, extraction, feedback, synchrotron

230

G.B. Christian, D.R. Bett, B. Constance, M.R. Davis
JAI, Oxford, United Kingdom
R. Apsimon, P. Burrows, A. Gerbershagen, C. Perry
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
J. Resta-López
IFIC, Valencia, Spain

Instabilities associated with beam-size blow-up have previously been observed with multi-bunch beam in the damping ring (DR) of the KEK Accelerator Test Facility (ATF). A system has been developed to monitor such instabilities, utilising an ATF stripline beam position monitor (BPM) in the DR, and BPM processor hardware designed for the FONT upstream feedback system in the ATF extraction line. The system is designed to record the horizontal and/or vertical positions of up to three bunches in the DR in single-bunch multi-train mode or the head bunch of up to three trains in multi-bunch mode, with a bunch spacing of 5.6 ns. The FPGA firmware and data acquisition software were modified to record turn-by-turn data for up to six channels and 1–3 bunches in the DR. The maximum memory configuration on the FPGA allows 131071 bunch-turn-channels of data to be recorded from a particular machine pulse, and the system has the capability to select only certain turns at a regular interval in which to record data, in order to zoom out and cover the entire period of the damping cycle at the ATF. An overview of the system and initial results will be presented.

TUPD13

CLIC Drive Beam Position Monitor

electron, linac, luminosity, coupling

326

S.R. Smith, A. Cappelletti, D. Gudkov, L. Søby, I. Syratchev
CERN, Geneva, Switzerland
S.R. Smith
SLAC, Menlo Park, California, USA

Funding: Work supported by Department of Energy contract DE-AC02-76SF00515
CLIC, an electron-positron linear collider proposed to probe the TeV energy scale, is based on a two-beam scheme where RF power to accelerate a high energy luminosity beam is extracted from a high current drive beam. The drive beam is efficiently generated in a long train at modest frequency and current then compressed in length and multiplied in frequency via bunch interleaving. The drive beam decelerator requires >40000 quadrupoles, each holding a beam position monitor (BPM). Though resolution requirements are modest (2 microns) these BPMs face several challenges. They must be compact and inexpensive. They must operate below waveguide cutoff to insure locality of position signals, ruling out processing at the natural 12 GHz bunch spacing frequency. Wakefields must be kept low. We find compact conventional stripline BPM with signals processed below 40 MHz can meet requirements. Choices of mechanical design, operating frequency, bandwidth, calibration, and processing algorithm are presented. Calculations of wakes and trapped modes and damping are discussed.

TUPD56

High Resolution SR Profile Monitor at ATF2 Extraction Line

extraction, emittance, background, controls

434

T. Naito, T.M. Mitsuhashi
KEK, Ibaraki, Japan

The profile monitor using visible light of the SR at ATF2 extraction line has been developed. KEK-ATF is a facility to produce extremely low emittance beam for the linear collider. The emittance in the damping ring is ex=1x10^-9 m and ey=1x10{-11} m, respectively. The ATF2 extraction line is a transport line to study the Final focus system for the linear collider. The designed beam size at the profile monitor is 230 μm in horizontal and 13 μm in vertical. We used a wide aperture optical system to reduce the Rayleigh limit of the optical system. The performance of the monitor is reported.