DIPAC2011 - List of Keywords (extraction)

Paper	Title	Other Keywords	Page
MOOC02	Cavity BPM System for ATF2	cavity, monitoring, quadrupole, EPICS	23
	A. Lyapin, R. Ainsworth, S.T. Boogert, G.E. Boorman, F.J. Cullinan, N.Y. Joshi JAI, Egham, Surrey, United Kingdom A.S. Aryshev, Y. Honda, T. Tauchi, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan J.C. Frisch, D.J. McCormick, J. Nelson, T.J. Smith, G.R. White SLAC, Menlo Park, California, USA A. Heo, E.-S. Kim, H.-S. Kim, Y.I. Kim KNU, Deagu, Republic of Korea M.C. Ross Fermilab, Batavia, USA
	In this paper we summarise our 2-year experience operating the Cavity Beam Position Monitor (CBPM) system at the Accelerator Test Facility (ATF) in KEK. The system currently consists of 41 C and S-band CBPMs and is the main diagnostic tool for the new ATF2 extraction beamline. We concentrate on issues related to the scale of the system and also consider long-term effects, most of which are undetectable or insignificant in smaller experimental prototype systems. We consistently show sub-micron BPM resolutions and week-to-week scale drifts of an order of 1%.
	Slides MOOC02 [2.075 MB]

MOPD02	The CNAO Qualification Monitor	synchrotron, power-supply, proton, controls	32
	C. Viviani, G. Balbinot, J. Bosser, M. Caldara, H. Caracciolo, M.A. Garella, V. Lante, A. Parravicini, M. Pullia CNAO Foundation, Milan, Italy
	The CNAO (Centro Nazionale di Adroterapia Oncologica) Foundation is the first Italian center for deep hadrontherapy. It will treat patients using Protons and Carbon ions in the next coming months. Patient safety is the first priority and many diagnostics devices have been developed to guarantee it. This work presents the so-called Qualification Monitor (QM). It is mounted in the common part of the four extraction lines, in front of the Chopper Dump, and it aims to qualify the extracted beam profile and intensity, before sending it to the treatment rooms. It is made of two different detectors: the first one, called Qualification Profile Monitor (QPM), is made by two dimensional harp of scintillating fibers to measure horizontal and vertical profiles. The second one, named Qualification Intensity Monitor (QIM) is a scintillating plate for intensity measurement. At the beginning of each extracted spill the beam is dumped on the Chopper Dump and it hit the QM. Only a positive result from beam qualification allows to switch on Chopper magnets and to send the beam to the patient. The QM is working with beam from some months, first results and future upgrades are presented.

MOPD30	Bunch Length Measurement for PETRA III Light Source Storage Ring	synchrotron, ion, vacuum, radiation	113
	H.-C. Schröder, A. Affeldt, H.P. Gausepohl, G. Kube, G. Priebe DESY, Hamburg, Germany
	To fulfill the demand for a very high brilliance synchrotron light source, it is required, that the individual particle bunches, used to create the synchrotron light in special undulator sections, do not exceed certain limits in linear dimension and divergence during the storage time. The bunch length measurement in the visible region of the spectrum is the sole system to measure the longitudinal beam parameter needed for a complete description of the behavior of the PETRAIII positron beam. A detailed description of the dipole magnet visible synchrotron light extraction, the light transport and the analysis by means of a Streak Camera System (SCS) in the context of the PETRAIII storage ring is given. The influence of the custom designed apochromatic refractive optics transport line on the time resolution of the bunch length measurement is discussed and values are given. The final time resolution of the whole system transport optics and Streak camera is shown to be not bigger than 4 ps. Several measurements from PETRAIII runs are presented and results of the bunch length measurements are shown. The typical bunch length measured is about 40 ps.
	Poster MOPD30 [6.402 MB]

MOPD79	An FPGA-based Turn-by-Turn Beam Position Monitoring System for Studying Multiple Bunch Beams in the ATF Damping Ring	injection, damping, 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.

MOPD80	An FPGA-based Bunch-by-Bunch Position and Angle Feedback System at ATF2	feedback, kicker, linear-collider, collider	233
	G.B. Christian, R. Apsimon, D.R. Bett, B. Constance, M.R. Davis JAI, Oxford, United Kingdom P. Burrows, C. Perry Oxford University, Physics Department, Oxford, Oxon, United Kingdom A. Gerbershagen CERN, Geneva, Switzerland J. Resta-López IFIC, Valencia, Spain
	The FONT5 intra-train feedback system serves as a prototype for an interaction point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider. The system has been tested on the KEK Accelerator Test Facility (ATF) and is deployed to stabilise the beam orbit at the ATF2. The goal of this system is to correct both position and angle jitter in the vertical plane, providing stability of ~1 micron at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. An overview of the hardware, and the latest results from beam tests at ATF2, will be presented. The total latency of the system with coupled position and angle feedback loops operating simultaneously was measured to be approximately 140 ns. The greatest degree of correction observed was down to a jitter of 0.4 microns at one of the feedback BPMs, a factor of six compared to the uncorrected beam jitter, for a very high degree of bunch-to-bunch correlation.

TUPD26	Cavity-based Beam Diagnostics at ELSA	cavity, electron, resonance, target	362
	T.R. Pusch, F. Frommberger, W. Hillert, B. Neff ELSA, Bonn, Germany
	Funding: Funded by DFG SFB/TR 16 Online monitoring of the intensity and position of an electron beam of a few hundred pA in the experiment beamlines at the ELSA facility is enabled by a system of resonant cavities. The position signal extracted from the resonators amounts to about 10^-19 W for 0.1 mm displacement at a beam current of 400 pA. It is separated from noise by phase-sensitive detection in a lock-in amplifier. The beam's position is obtained with a precision of one tenth of a millimeter, the signal strength being normalized by a beam current measurement with an uncertainty of a few pA. Via frequency mixing, the cavity signal of 1.5 GHz is converted down to a frequency below 100 kHz in order to be accepted by the amplifier, requiring a local oscillator stabilized by a feedback loop to 10^-6 precision. Details of the measurement system are presented.

TUPD56	High Resolution SR Profile Monitor at ATF2 Extraction Line	emittance, background, controls, damping	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.

TUPD61	Multi Optical Transition Radiation System for ATF2	emittance, target, coupling, controls	446
	C. Blanch Gutierrez, J. Alabau-Gonzalvo, A. Faus-Golfe, J.J. García-Garrigós IFIC, Valencia, Spain J. Cruz, D.J. McCormick, G.R. White, M. Woodley SLAC, Menlo Park, California, USA
	Funding: FPA2010-21456-C02-00 In this paper we describe the calibration tests, software development and first measurements of a Multi Optical Transition Radiation System in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. First 2D emittance measurements have been made with success and the system is being used normally for coupling correction. 4D emittance reconstruction algorithm is under improvement and implementation before a systematic measurement campaign and comparison with wire scanners is done. This will be a definitive test of the OTR as a beam emittance diagnostic device, which will give the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter.

WEOA03	Detailed Experimental Characterization of an Ionization Profile Monitor	electron, ion, space-charge, target	547
	J. Egberts, P. Abbon, F. Jeanneau, J.-Ph. Mols, T. Papaevangelou CEA, Gif-sur-Yvette, France F. Becker, P. Forck, B. Walasek-Höhne GSI, Darmstadt, Germany J. Marroncle CEA/DSM/IRFU, France
	Funding: Marie Curie Fellowship by the EU In the frame of the International Fusion Material Irradiation Facility (IFMIF), a prototype for a non-interceptive transverse beam profile monitor based on residual gas ionization (IPM) has been built and characterized in detail. We present results of test measurements performed at CEA Saclay with 80 keV protons in a cw beam of up to 10 mA and at GSI Darmstadt with pulsed Ca¹⁰⁺, Xe²¹⁺ and U²⁸⁺ beams of up to 1.6 mA at 5 MeV/u. The effects of N₂, and different rare gases in the pressure range from 4•10^-7 mbar to 5•10^-4 mbar have been investigated. The signal was read by different electronic cards, based on linear and logarithmic amplifiers as well as on charge integration. Furthermore the extraction voltage of the IPM-field-box was varied between 0.5 and 5 kV. Beam profiles were investigated with respect to signal intensity and profile shape and were compared to a SEM-grid and a Beam Induced Fluorescence monitor. Profiles of all monitors match nicely for the residual gases with differences in beam width well below 5%. Additional tests on the characteristics of the IPM have been performed and will be presented as well.
	Slides WEOA03 [1.964 MB]

Paper

Title

Other Keywords

Page

MOOC02

Cavity BPM System for ATF2

cavity, monitoring, quadrupole, EPICS

23

A. Lyapin, R. Ainsworth, S.T. Boogert, G.E. Boorman, F.J. Cullinan, N.Y. Joshi
JAI, Egham, Surrey, United Kingdom
A.S. Aryshev, Y. Honda, T. Tauchi, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan
J.C. Frisch, D.J. McCormick, J. Nelson, T.J. Smith, G.R. White
SLAC, Menlo Park, California, USA
A. Heo, E.-S. Kim, H.-S. Kim, Y.I. Kim
KNU, Deagu, Republic of Korea
M.C. Ross
Fermilab, Batavia, USA

In this paper we summarise our 2-year experience operating the Cavity Beam Position Monitor (CBPM) system at the Accelerator Test Facility (ATF) in KEK. The system currently consists of 41 C and S-band CBPMs and is the main diagnostic tool for the new ATF2 extraction beamline. We concentrate on issues related to the scale of the system and also consider long-term effects, most of which are undetectable or insignificant in smaller experimental prototype systems. We consistently show sub-micron BPM resolutions and week-to-week scale drifts of an order of 1%.

Slides MOOC02 [2.075 MB]

MOPD02

The CNAO Qualification Monitor

synchrotron, power-supply, proton, controls

32

C. Viviani, G. Balbinot, J. Bosser, M. Caldara, H. Caracciolo, M.A. Garella, V. Lante, A. Parravicini, M. Pullia
CNAO Foundation, Milan, Italy

The CNAO (Centro Nazionale di Adroterapia Oncologica) Foundation is the first Italian center for deep hadrontherapy. It will treat patients using Protons and Carbon ions in the next coming months. Patient safety is the first priority and many diagnostics devices have been developed to guarantee it. This work presents the so-called Qualification Monitor (QM). It is mounted in the common part of the four extraction lines, in front of the Chopper Dump, and it aims to qualify the extracted beam profile and intensity, before sending it to the treatment rooms. It is made of two different detectors: the first one, called Qualification Profile Monitor (QPM), is made by two dimensional harp of scintillating fibers to measure horizontal and vertical profiles. The second one, named Qualification Intensity Monitor (QIM) is a scintillating plate for intensity measurement. At the beginning of each extracted spill the beam is dumped on the Chopper Dump and it hit the QM. Only a positive result from beam qualification allows to switch on Chopper magnets and to send the beam to the patient. The QM is working with beam from some months, first results and future upgrades are presented.

MOPD30

Bunch Length Measurement for PETRA III Light Source Storage Ring

synchrotron, ion, vacuum, radiation

113

H.-C. Schröder, A. Affeldt, H.P. Gausepohl, G. Kube, G. Priebe
DESY, Hamburg, Germany

To fulfill the demand for a very high brilliance synchrotron light source, it is required, that the individual particle bunches, used to create the synchrotron light in special undulator sections, do not exceed certain limits in linear dimension and divergence during the storage time. The bunch length measurement in the visible region of the spectrum is the sole system to measure the longitudinal beam parameter needed for a complete description of the behavior of the PETRAIII positron beam. A detailed description of the dipole magnet visible synchrotron light extraction, the light transport and the analysis by means of a Streak Camera System (SCS) in the context of the PETRAIII storage ring is given. The influence of the custom designed apochromatic refractive optics transport line on the time resolution of the bunch length measurement is discussed and values are given. The final time resolution of the whole system transport optics and Streak camera is shown to be not bigger than 4 ps. Several measurements from PETRAIII runs are presented and results of the bunch length measurements are shown. The typical bunch length measured is about 40 ps.

Poster MOPD30 [6.402 MB]

MOPD79

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

injection, damping, 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.

MOPD80

An FPGA-based Bunch-by-Bunch Position and Angle Feedback System at ATF2

feedback, kicker, linear-collider, collider

233

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

The FONT5 intra-train feedback system serves as a prototype for an interaction point beam-based feedback system for future electron-positron colliders, such as the International Linear Collider. The system has been tested on the KEK Accelerator Test Facility (ATF) and is deployed to stabilise the beam orbit at the ATF2. The goal of this system is to correct both position and angle jitter in the vertical plane, providing stability of ~1 micron at the entrance to the ATF2 final-focus system. The system comprises three stripline beam position monitors (BPMs) and two stripline kickers, custom low-latency analogue front-end BPM processors, a custom FPGA-based digital processing board with fast ADCs, and custom kicker-drive amplifiers. An overview of the hardware, and the latest results from beam tests at ATF2, will be presented. The total latency of the system with coupled position and angle feedback loops operating simultaneously was measured to be approximately 140 ns. The greatest degree of correction observed was down to a jitter of 0.4 microns at one of the feedback BPMs, a factor of six compared to the uncorrected beam jitter, for a very high degree of bunch-to-bunch correlation.

TUPD26

Cavity-based Beam Diagnostics at ELSA

cavity, electron, resonance, target

362

T.R. Pusch, F. Frommberger, W. Hillert, B. Neff
ELSA, Bonn, Germany

Funding: Funded by DFG SFB/TR 16
Online monitoring of the intensity and position of an electron beam of a few hundred pA in the experiment beamlines at the ELSA facility is enabled by a system of resonant cavities. The position signal extracted from the resonators amounts to about 10^-19 W for 0.1 mm displacement at a beam current of 400 pA. It is separated from noise by phase-sensitive detection in a lock-in amplifier. The beam's position is obtained with a precision of one tenth of a millimeter, the signal strength being normalized by a beam current measurement with an uncertainty of a few pA. Via frequency mixing, the cavity signal of 1.5 GHz is converted down to a frequency below 100 kHz in order to be accepted by the amplifier, requiring a local oscillator stabilized by a feedback loop to 10^-6 precision. Details of the measurement system are presented.

TUPD56

High Resolution SR Profile Monitor at ATF2 Extraction Line

emittance, background, controls, damping

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.

TUPD61

Multi Optical Transition Radiation System for ATF2

emittance, target, coupling, controls

446

C. Blanch Gutierrez, J. Alabau-Gonzalvo, A. Faus-Golfe, J.J. García-Garrigós
IFIC, Valencia, Spain
J. Cruz, D.J. McCormick, G.R. White, M. Woodley
SLAC, Menlo Park, California, USA

Funding: FPA2010-21456-C02-00
In this paper we describe the calibration tests, software development and first measurements of a Multi Optical Transition Radiation System in the beam diagnostic section of the Extraction (EXT) line of ATF2, close to the multi wire scanner system. First 2D emittance measurements have been made with success and the system is being used normally for coupling correction. 4D emittance reconstruction algorithm is under improvement and implementation before a systematic measurement campaign and comparison with wire scanners is done. This will be a definitive test of the OTR as a beam emittance diagnostic device, which will give the ability to measure the beam emittance with high statistics, giving a low error and a good understanding of emittance jitter.

WEOA03

Detailed Experimental Characterization of an Ionization Profile Monitor

electron, ion, space-charge, target

547

J. Egberts, P. Abbon, F. Jeanneau, J.-Ph. Mols, T. Papaevangelou
CEA, Gif-sur-Yvette, France
F. Becker, P. Forck, B. Walasek-Höhne
GSI, Darmstadt, Germany
J. Marroncle
CEA/DSM/IRFU, France

Funding: Marie Curie Fellowship by the EU
In the frame of the International Fusion Material Irradiation Facility (IFMIF), a prototype for a non-interceptive transverse beam profile monitor based on residual gas ionization (IPM) has been built and characterized in detail. We present results of test measurements performed at CEA Saclay with 80 keV protons in a cw beam of up to 10 mA and at GSI Darmstadt with pulsed Ca¹⁰⁺, Xe²¹⁺ and U²⁸⁺ beams of up to 1.6 mA at 5 MeV/u. The effects of N₂, and different rare gases in the pressure range from 4•10^-7 mbar to 5•10^-4 mbar have been investigated. The signal was read by different electronic cards, based on linear and logarithmic amplifiers as well as on charge integration. Furthermore the extraction voltage of the IPM-field-box was varied between 0.5 and 5 kV. Beam profiles were investigated with respect to signal intensity and profile shape and were compared to a SEM-grid and a Beam Induced Fluorescence monitor. Profiles of all monitors match nicely for the residual gases with differences in beam width well below 5%. Additional tests on the characteristics of the IPM have been performed and will be presented as well.

Slides WEOA03 [1.964 MB]