DIPAC2011 - List of Keywords (beam-losses)

Paper	Title	Other Keywords	Page
MOPD05	Beam Diagnostic Layout for SIS100 at FAIR	ion, diagnostics, pick-up, proton	41
	M. Schwickert, P. Forck, T. Hoffmann, P. Kowina, H. Reeg GSI, Darmstadt, Germany
	The SIS100 heavy ion synchrotron will be the central machine of the FAIR (Facility for Antiprotons and Ions Research) project currently designed at GSI. The unique features of SIS100, like e.g. the acceleration of high intensity beams of 2.5·10¹³ protons and 5·10¹¹ Uranium ions near the space charge limit, the anticipated large tune spread, extreme UHV conditions of the cryogenic system for superconducting magnets and fast ramp rates of 4 T/s, make challenging demands on the beam diagnostic components. This contribution describes the conceptual design for SIS100 beam diagnostics and reports on the present status of prototype studies. Exemplarily the progress concerning beam position monitors, beam current transformers and beam-loss monitors is presented.

MOPD18	Embedded Collimator Beam Position Monitors	vacuum, collimation, impedance, proton	80
	C.B. Boccard, A. Bertarelli, A. Dallocchio, M. Gasior, L. Gentini, A.A. Nosych CERN, Geneva, Switzerland
	The LHC collimation system is crucial for safe and reliable operation of proton beams with 350 MJ stored energy. Currently the collimator set-up is performed by observing beam losses when approaching the collimator jaws to the beam. For all 100 LHC movable collimators the procedure may take several hours and since it has to be repeated whenever the beam configuration changes significantly, the collimator setup has an important impact on the overall machine operation efficiency. To reduce the collimator setup time by two orders of magnitude the next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. This paper describes the BPM design and presents prototype results obtained with beam in the CERN-SPS.
	Poster MOPD18 [1.729 MB]

MOPD41	A Fast CVD Diamond Beam Loss Monitor for LHC	radiation, collimation, controls, instrumentation	143
	E. Griesmayer, B. Dehning, D. Dobos, E. Effinger, H. Pernegger CERN, Geneva, Switzerland
	Chemical Vapour Deposition (CVD) diamond detectors were installed in the collimation area of the CERN LHC to study their feasibility as Fast Beam Loss Monitors in a high-radiation environment. The detectors were configured with a fast, radiation-hard pre-amplifier with a bandwidth of 2 GHz. The readout was via an oscilloscope with a bandwidth of 1 GHz and a sampling rate of 5 GSPS. Despite the 250 m cable run from the detectors to the oscilloscope, single MIPs were resolved with a 2 ns rise time, a pulse width of 10 ns and a time resolution of less than 1 ns. Two modes of operation were applied. For the analysis of unexpected beam aborts, the loss profile was recorded in a 1 ms buffer and, for nominal operation, the histogram of the time structure of the losses was recorded in synchronism with the LHC period of 89.2 μs. Measurements during the LHC start-up (February to December 2010) are presented. The Diamond Monitors gave an unprecedented insight into the time structure of the beam losses resolving the 400 MHz RF frequency as well as the nominal bunch separation of 25 ns. In future, these detectors will be used to study ghost bunches and particles in the 3 μs abort gap.

MOPD64	High Quality Measurements of Beam Lifetime, Instant-Partial-Beam Losses and Charge-Accumulation with the New ESRF BPM System	injection, cavity, storage-ring, controls	194
	K.B. Scheidt, F. Ewald, B. Joly ESRF, Grenoble, France
	The BPM system of the ESRF Storage Ring, that was entirely replaced by 224 units of the Libera-Brilliance system in 2009, is now also being used for precise and fast measurements of the Beam Lifetime and so-called Instant-Partial-BeamLosses. This is possible by the use of the Sum signal of the four BPM buttons on each of the 224 BPM stations in the Ring. This paper will describe the strong advantages in terms of response time, but also the precautions and the limitations of this particular use. Results will show the ultimate attainable performances and a detailed comparison with that of three independent DC current transformers also installed in the Ring. The same Sum signal is also usable for precise measurement of Accumulated Charge during the injection process and results of this will also be presented.

MOPD90	Cause Identification of Beam Losses in PETRA III by Time Correlation of Alarms	undulator, status, dumping, power-supply	257
	T. Lensch, M. Werner DESY, Hamburg, Germany
	PETRA III is a high brilliant synchrotron light-source operating at 6 GeV at the DESY site in Hamburg. The Machine Protection System (MPS) of PETRA III is under operation since the beginning of the commissioning of PETRA III in April 2009. Under certain alarm conditions the MPS generates a dump command and protects the machine against damage. As a functional extension the MPS hardware examines the time correlation of alarm sequences after a beam loss. The alarm sequences are evaluated in a software based system so that the cause of a beam loss can be displayed in the control room immediately. This paper describes the hardware implementation as well as the software rules.
	Poster MOPD90 [0.548 MB]

TUPD42	Design and Experiences with the Beam Condition Monitor as Protection System in the CMS Experiment of the LHC	background, vacuum, monitoring, radiation	398
	M. Guthoff CERN, Geneva, Switzerland
	The Beam Condition Monitor (BCM) is used as protection system. In order to prevent damage to the pixel and tracker detectors it can trigger a beam dump when extremely high beam losses occur. The system consists of BCM1L with 4 diamonds per side at 1.8m away from the interaction point and BCM2 with 4 inner and 8 outer diamonds per side at 14.4m away from the interaction point. As detector material poly-crystalline CVD diamonds are used. The readout electronics is identical to the Beam Loss Monitor (BLM) system of the LHC. With cross calibration measurements a direct comparison between the BLM and the BCM systems is possible. The BCM system is therefore a transparent extension of the BLM system into the CMS cavern. The BCM2 system has been active in the beam abort system since the beginning of collisions at the LHC. Design and performance of the system during the run of the LHC so far will be presented. *on behalf of the CMS BRM group.
	Poster TUPD42 [0.736 MB]

TUPD43	XFEL Beam Loss Monitor System	electron, undulator, controls, high-voltage	401
	A. Kaukher, I. Krouptchenkov, B. Michalek, D. Nölle, H. Tiessen DESY, Hamburg, Germany
	European XFEL will have a sophisticated Machine Protection System, part of which - Beam Loss Monitors(BLM). The monitors will detect losses of electron beam, in order to protect the components of the XFEL from damage and excessive activation. For protection of undulators, BLMs with a scintillator bar will be used. BLMs at places with high radiation load will be equipped with fused silica rods. Beam dumps of the XFEL will be instrumented with glass-fiber BLMs. The BLMs were tested with an electron test-beam at DESY, as well as at FLASH. Due to large amount of light produced by scintillator and high gain of the used photomultiplier, no optical grease is needed in front of the photomultiplier' window, while typical cathode voltage is only 500-600 volt. The prototype with quartz glass was typically operated at higher cathode voltage. Good operation of all three types of BLMs prototypes was obtained. It is planned to use same monitors also for the FLASH2 project. Current status of the XFEL BLM system development will be presented.

TUPD96	Fast and Critical Detection Devices Planned for the Machine Protection System at the Facility for Rare Isotope Beams	linac, controls, status, EPICS	533
	G. Kiupel, S. Assadi, T.D. Brown, P. Chu, J.L. Crisp, S. Peng, M.W. Stettler, Y. Zhang FRIB, East Lansing, Michigan, USA
	Funding: Work supported by US DOE Cooperative Agreement DE-SC0000661 The Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU) will use a 400 kW, heavy-ion cw linac to produce rare isotopes in support of a rich program of fundamental research. In the event of operational failures, the Machine Protection System (MPS) shuts off the beam within microseconds to control beam losses that may damage accelerator components. The operational mode is distributed to all fast and critical devices that have multiple hardware checkpoints and comparators. A relational database provides the framework for the development of the MPS management application. In this paper, we present the FRIB MPS architecture, plans and implementation.

Paper

Title

Other Keywords

Page

MOPD05

Beam Diagnostic Layout for SIS100 at FAIR

ion, diagnostics, pick-up, proton

41

M. Schwickert, P. Forck, T. Hoffmann, P. Kowina, H. Reeg
GSI, Darmstadt, Germany

The SIS100 heavy ion synchrotron will be the central machine of the FAIR (Facility for Antiprotons and Ions Research) project currently designed at GSI. The unique features of SIS100, like e.g. the acceleration of high intensity beams of 2.5·10¹³ protons and 5·10¹¹ Uranium ions near the space charge limit, the anticipated large tune spread, extreme UHV conditions of the cryogenic system for superconducting magnets and fast ramp rates of 4 T/s, make challenging demands on the beam diagnostic components. This contribution describes the conceptual design for SIS100 beam diagnostics and reports on the present status of prototype studies. Exemplarily the progress concerning beam position monitors, beam current transformers and beam-loss monitors is presented.

MOPD18

Embedded Collimator Beam Position Monitors

vacuum, collimation, impedance, proton

80

C.B. Boccard, A. Bertarelli, A. Dallocchio, M. Gasior, L. Gentini, A.A. Nosych
CERN, Geneva, Switzerland

The LHC collimation system is crucial for safe and reliable operation of proton beams with 350 MJ stored energy. Currently the collimator set-up is performed by observing beam losses when approaching the collimator jaws to the beam. For all 100 LHC movable collimators the procedure may take several hours and since it has to be repeated whenever the beam configuration changes significantly, the collimator setup has an important impact on the overall machine operation efficiency. To reduce the collimator setup time by two orders of magnitude the next generation of the LHC collimators will be equipped with button beam position monitors (BPMs) embedded into the collimator jaws. This paper describes the BPM design and presents prototype results obtained with beam in the CERN-SPS.

Poster MOPD18 [1.729 MB]

MOPD41

A Fast CVD Diamond Beam Loss Monitor for LHC

radiation, collimation, controls, instrumentation

143

E. Griesmayer, B. Dehning, D. Dobos, E. Effinger, H. Pernegger
CERN, Geneva, Switzerland

Chemical Vapour Deposition (CVD) diamond detectors were installed in the collimation area of the CERN LHC to study their feasibility as Fast Beam Loss Monitors in a high-radiation environment. The detectors were configured with a fast, radiation-hard pre-amplifier with a bandwidth of 2 GHz. The readout was via an oscilloscope with a bandwidth of 1 GHz and a sampling rate of 5 GSPS. Despite the 250 m cable run from the detectors to the oscilloscope, single MIPs were resolved with a 2 ns rise time, a pulse width of 10 ns and a time resolution of less than 1 ns. Two modes of operation were applied. For the analysis of unexpected beam aborts, the loss profile was recorded in a 1 ms buffer and, for nominal operation, the histogram of the time structure of the losses was recorded in synchronism with the LHC period of 89.2 μs. Measurements during the LHC start-up (February to December 2010) are presented. The Diamond Monitors gave an unprecedented insight into the time structure of the beam losses resolving the 400 MHz RF frequency as well as the nominal bunch separation of 25 ns. In future, these detectors will be used to study ghost bunches and particles in the 3 μs abort gap.

MOPD64

High Quality Measurements of Beam Lifetime, Instant-Partial-Beam Losses and Charge-Accumulation with the New ESRF BPM System

injection, cavity, storage-ring, controls

194

K.B. Scheidt, F. Ewald, B. Joly
ESRF, Grenoble, France

The BPM system of the ESRF Storage Ring, that was entirely replaced by 224 units of the Libera-Brilliance system in 2009, is now also being used for precise and fast measurements of the Beam Lifetime and so-called Instant-Partial-BeamLosses. This is possible by the use of the Sum signal of the four BPM buttons on each of the 224 BPM stations in the Ring. This paper will describe the strong advantages in terms of response time, but also the precautions and the limitations of this particular use. Results will show the ultimate attainable performances and a detailed comparison with that of three independent DC current transformers also installed in the Ring. The same Sum signal is also usable for precise measurement of Accumulated Charge during the injection process and results of this will also be presented.

MOPD90

Cause Identification of Beam Losses in PETRA III by Time Correlation of Alarms

undulator, status, dumping, power-supply

257

T. Lensch, M. Werner
DESY, Hamburg, Germany

PETRA III is a high brilliant synchrotron light-source operating at 6 GeV at the DESY site in Hamburg. The Machine Protection System (MPS) of PETRA III is under operation since the beginning of the commissioning of PETRA III in April 2009. Under certain alarm conditions the MPS generates a dump command and protects the machine against damage. As a functional extension the MPS hardware examines the time correlation of alarm sequences after a beam loss. The alarm sequences are evaluated in a software based system so that the cause of a beam loss can be displayed in the control room immediately. This paper describes the hardware implementation as well as the software rules.

Poster MOPD90 [0.548 MB]

TUPD42

Design and Experiences with the Beam Condition Monitor as Protection System in the CMS Experiment of the LHC

background, vacuum, monitoring, radiation

398

M. Guthoff
CERN, Geneva, Switzerland

The Beam Condition Monitor (BCM) is used as protection system. In order to prevent damage to the pixel and tracker detectors it can trigger a beam dump when extremely high beam losses occur. The system consists of BCM1L with 4 diamonds per side at 1.8m away from the interaction point and BCM2 with 4 inner and 8 outer diamonds per side at 14.4m away from the interaction point. As detector material poly-crystalline CVD diamonds are used. The readout electronics is identical to the Beam Loss Monitor (BLM) system of the LHC. With cross calibration measurements a direct comparison between the BLM and the BCM systems is possible. The BCM system is therefore a transparent extension of the BLM system into the CMS cavern. The BCM2 system has been active in the beam abort system since the beginning of collisions at the LHC. Design and performance of the system during the run of the LHC so far will be presented.
*on behalf of the CMS BRM group.

Poster TUPD42 [0.736 MB]

TUPD43

XFEL Beam Loss Monitor System

electron, undulator, controls, high-voltage

401

A. Kaukher, I. Krouptchenkov, B. Michalek, D. Nölle, H. Tiessen
DESY, Hamburg, Germany

European XFEL will have a sophisticated Machine Protection System, part of which - Beam Loss Monitors(BLM). The monitors will detect losses of electron beam, in order to protect the components of the XFEL from damage and excessive activation. For protection of undulators, BLMs with a scintillator bar will be used. BLMs at places with high radiation load will be equipped with fused silica rods. Beam dumps of the XFEL will be instrumented with glass-fiber BLMs. The BLMs were tested with an electron test-beam at DESY, as well as at FLASH. Due to large amount of light produced by scintillator and high gain of the used photomultiplier, no optical grease is needed in front of the photomultiplier' window, while typical cathode voltage is only 500-600 volt. The prototype with quartz glass was typically operated at higher cathode voltage. Good operation of all three types of BLMs prototypes was obtained. It is planned to use same monitors also for the FLASH2 project. Current status of the XFEL BLM system development will be presented.

TUPD96

Fast and Critical Detection Devices Planned for the Machine Protection System at the Facility for Rare Isotope Beams

linac, controls, status, EPICS

533

G. Kiupel, S. Assadi, T.D. Brown, P. Chu, J.L. Crisp, S. Peng, M.W. Stettler, Y. Zhang
FRIB, East Lansing, Michigan, USA

Funding: Work supported by US DOE Cooperative Agreement DE-SC0000661
The Facility for Rare Isotope Beams (FRIB) at Michigan State University (MSU) will use a 400 kW, heavy-ion cw linac to produce rare isotopes in support of a rich program of fundamental research. In the event of operational failures, the Machine Protection System (MPS) shuts off the beam within microseconds to control beam losses that may damage accelerator components. The operational mode is distributed to all fast and critical devices that have multiple hardware checkpoints and comparators. A relational database provides the framework for the development of the MPS management application. In this paper, we present the FRIB MPS architecture, plans and implementation.