IBIC2013 - List of Keywords (DIAMOND)

Paper	Title	Other Keywords	Page
MOPC10	Optimization of NSLS-II Blade X-ray Beam Position Monitors: From Photoemission Type to Diamond Detector	undulator, radiation, photon, beam-position	67
	P. Ilinski BNL, Upton, Long Island, New York, USA
	Optimization of blade type X-ray Beam Position Monitors (XBPM) was performed for NSLS-II undulator IVU20. Blade material, conﬁguration and operation principle were analyzed. Optimization is based on calculation of the XBPM signal spatial distribution. Along with standard photo-emission blades, Diamond Detector Blade (DDB) was examined as XBPM signal source. Analyses revealed, that Diamond Detector Blade XBPM would allow to overcome drawbacks of the photo-emission type XBPMs.

MOPC34	Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source	optics, radiation, longitudinal, storage-ring	143
	W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom R. Bartolini, P. Karataev JAI, Oxford, United Kingdom P. Karataev Royal Holloway, University of London, Surrey, United Kingdom
	An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPC43	Performance of Detectors using Diamond Sensors at the LHC and CMS	beam-losses, LHC, luminosity, injection	174
	M. Hempel BTU, Cottbus, Germany T. Baer, A.E. Dabrowski CERN, Geneva, Switzerland E. Griesmayer ATI, Wien, Austria W. Lange, O. Novgorodova DESY Zeuthen, Zeuthen, Germany W. Lohmann DESY, Hamburg, Germany N.J. Odell NU, Evanston, USA D.P. Stickland PU, Princeton, New Jersey, USA
	Diamond detectors are used as beam loss and luminosity monitors for CMS and LHC. A time resolution in the nanosecond range allows to detect beam losses and luminosities of single bunches. The radiation hardness and negligible temperature dependence allow the usage of diamond sensors in high radiation fields without cooling. Two different diamond detector types are installed at LHC and CMS. One is based on pCVD diamonds and installed at different locations in the LHC tunnel for beam loss monitoring. Measurements of these detectors are used to perform a bunch-by-bunch beam loss analysis. They allow to disentangle the origin of beam losses. The second type uses sCVD diamonds and is located inside CMS for van-der-Meer scan, beam halo and online luminosity monitoring and around the LHC tunnel for beam loss observation. Results on the performance of these detectors will be presented and examples of the use for analyzing the beam conditions will be given. In order to persist the enhanced requirements of the LHC after the long shutdown, e.g. higher luminosity, an upgrade of the detectors is required. The concept of the new detectors will be presented and first results will be shown.
	Poster MOPC43 [0.721 MB]

MOPC45	A Prototype Readout System for the Diamond Beam Loss Monitors at LHC	beam-losses, LHC, injection, proton	182
	E. Effinger, T. Baer, B. Dehning, R. Schmidt CERN, Geneva, Switzerland H. Frais-Kölbl FH WN, Wiener Neustadt, Austria E. Griesmayer ATI, Wien, Austria P. Kavrigin CIVIDEC Instrumentation, Wien, Austria
	Diamond Beam Loss Monitors are used at the LHC for the measurement of fast beam losses. Results from specimen LHC loss measurements are presented in this talk. The bunch-to-bunch loss measurements make full use of the fast signal response of the diamond detectors with 1 ns time resolution and 6.7 ns double pulse resolution. The data processing is done with a dedicated readout system, which was designed and optimized for particular applications with the diamond beam loss monitors. This FPGA-based system provides on-line, real-time, and dead-time-free data processing. Several examples are presented: the Time Loss Histogram with 1.6 ns binning provides beam loss measurements that are synchronized with the revolution period throughout the full operational LHC cycle. The Post Mortem Recorder with a sampling frequency of 1 GS/s allows beam-loss-based tune estimates for all bunches in parallel. Future applications and upgrades are discussed.
	Poster MOPC45 [0.778 MB]

MOPF23	Quantifying Dissipated Power From Wake Field Losses in Diagnostics Structures	simulation, impedance, resonance, single-bunch	259
	A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom
	As a charged particle beam passes through structures, wake fields can deposit a fraction of the energy carried by the beam as characterised by the wake loss factor. Some part of the deposited energy will be emitted into the beam pipe, some part can be coupled out of signal ports and some part will be absorbed by the materials of the structures. With increasingly higher stored currents, we require a better understanding of where all the energy deposited by wake losses ends up in order to avoid damaging components. This is of particular concern for diagnostics structures as they are often designed to couple a small fraction of energy from the beam, which makes them susceptible to thermal damage due to increased localised losses. We will detail the simulation and analysis approach which we have developed to quantify power deposition within structures. As an example the analysis of a beam position monitor pickup block of the Diamond storage ring is shown.
	Poster MOPF23 [0.249 MB]

TUPC10	Operation of Diamond Light Source XBPMs with Zero Bias	electron, photon, synchrotron, beam-position	376
	C. Bloomer, G. Rehm Diamond, Oxfordshire, United Kingdom
	Tungsten blade X-ray Beam Position Monitors (XBPMs) have been used at Diamond Light Source since 2007, however a long-standing problem with these devices has been the growth of leakage current through the ceramic insulation within the XBPMs over time, often becoming greater than 10% of the signal current after a few years of operation. The growth of these leakage currents has been found to be exacerbated by the application of a negative bias (-70V) to the tungsten blades, a bias suggested for optimum position sensitivity. This bias is applied in order to accelerate free electrons away from the surface of the blades and to prevent cross-talk, however, we have found that the operation of the XBPMs without bias has negligible impact on our measurements. Removal of the bias has been found to prevent the growth of leakage currents over time, and can also significantly reduce the cost of our signal acquisition by removing the need for a low-current amplifier with a bias supply.
	Poster TUPC10 [0.455 MB]

WEPC10	Capability Upgrade of the Diamond Transverse Multibunch Feedback	feedback, controls, transverse, FIR	682
	M.G. Abbott, G. Rehm, I.S. Uzun Diamond, Oxfordshire, United Kingdom
	We describe an upgrade to the Transverse Multi-Bunch Feedback processor used at Diamond for control of multi-bunch instabilities and measurement of betatron tunes. The new system will improve both feedback and diagnostic capabilities. Bunch by bunch selectable control over feedback filters, gain and excitation will allow finer control over feedback, allowing for example the single bunch in a hybrid or camshaft fill pattern to be controlled independently from the bunch train. It will also be possible to excite all bunches at a single frequency while simultaneously sweeping the excitation for tune measurement of a few selected bunches. The single frequency excitation can be used for bunch cleaning or continuous measurement of the beta-function. A simple programmable event sequencer will provide support for up to 8 steps of programmable sweeps and changes to feedback and excitation, allowing a variety of complex and precisely timed beam characterisation experiments including grow-damp measurements in unstable conditions.
	Poster WEPC10 [0.427 MB]

WEPC22	First Steps Towards a Fast Orbit Feedback at ALBA	feedback, ESRF, brilliance, simulation	727
	A. Olmos, S. Blanch-Torné, Z. Martí, J. Moldes, M. Muñoz, R. Petrocelli, X. Serra-Gallifa CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain A. Gutierrez-Milla UAB, Barcelona, Spain
	An optimum performance of the ALBA facility requires a beam orbit stability on the sub-micron level up to frequencies in the 100 Hz range. The Fast Orbit FeedBack system (FOFB) is designed to achieve such a stability. After investigation of possible system architecture, a decision has been taken that exploits the available in-house hardware. This “low-cost” first stage FOFB will be an ideal test-bench to learn about beam stabilization and find possible problems and improvements on it. This report explains the current lay-out and status of the FOFB at ALBA.
	Poster WEPC22 [3.107 MB]

WEPC43	Update on Beam Loss Monitoring at CTF3 for CLIC	CLIC, beam-losses, photon, quadrupole	787
	L.J. Devlin, S. Mallows, C.P. Welsch, E.N. del Busto Cockcroft Institute, Warrington, Cheshire, United Kingdom E. Branger Linköping University, Linköping, Sweden L.J. Devlin, S. Mallows, C.P. Welsch, E.N. del Busto The University of Liverpool, Liverpool, United Kingdom E. Effinger, E.B. Holzer, S. Mallows, E.N. del Busto CERN, Geneva, Switzerland
	Funding: Work supported by STFC Cockcroft Institute Core Grant No. ST/G008248/1 The primary role of the beam loss monitoring (BLM) system for the compact linear collider (CLIC) study is to work within the machine protection system. Due to the size of the CLIC facility, a BLM that covers large distances along the beamline is highly desirable, in particular for the CLIC drive beam decelerators, which would alternatively require some ~40,000 localised monitors. Therefore, an optical fiber BLM system is currently under investigation which can cover large sections of beamline at a time. A multimode fiber has been installed along the Test Beam Line at the CLIC test facility (CTF3) where the detection principle is based on the production of Cherenkov photons within the fiber resulting from beam loss and their subsequent transport along the fiber where they are then detected at the fiber ends using silicon photomultipliers. Several additional monitors including ACEMs, PEP-II and diamond detectors have also been installed. In this contribution the first results from the BLMs are presented, comparisons of the signals from each BLM are made and the possible achievable longitudinal resolution from the fiber BLM signal considering various loss patterns is discussed.

WEPC44	Operation of Silicon, Diamond and Liquid Helium Detectors in the Range of Room Temperature to 1.9 Kelvin and After an Irradiation Dose of Several Mega Gray	proton, LHC, beam-losses, CERN	791
	C. Kurfuerst, M.R. Bartosik, B. Dehning, T. Eisel, M. Sapinski CERN, Geneva, Switzerland V. Eremin IOFFE, St. Petersburg, Russia
	At the triplet magnets close to the interaction regions of the LHC, the current Beam Loss Monitoring system is sensitive to the debris from the collision points. For future beams with higher energy and intensity, the expected increase in luminosity and associated increase of the debris from interaction products is expected to compete with any quench-provoking beam losses from the primary proton beams. In order to distinguish between the two, it is proposed to locate the detectors as close as possible to the superconducting coil. The detectors therefore have to be located inside the cold mass of the superconducting magnets in superfluid helium at 1.9 K. Past measurements have shown that in a liquid helium chamber, diamond and silicon detectors are promising candidates for cryogenic beam loss monitors. This contribution will show the results from new high irradiation beam measurements at both room temperature and 1.9 Kelvin to reveal the radiation tolerance of these different detectors.

WEPF15	High-Power Tests at CesrTA of X-ray Optics Elements for SuperKEKB	simulation, optics, factory, LEFT	844
	J.W. Flanagan, A. Arinaga, H. Fukuma, H. Ikeda KEK, Ibaraki, Japan A. Lyndaker, D.P. Peterson, N.T. Rider Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	X-ray beam size monitors at SuperKEKB must withstand high, sustained incident power loads. Two prototype optics elements were fabricated and tested at CesrTA, using incident X-ray power densities comparable to those expected at the SuperKEKB LER. One element was based on a silicon substrate, the other a CVD diamond substrate, with each substrate supporting a coded aperture mask pattern in gold on its surface. The diamond substrate mask showed superior performance to the silicon substrate mask, with the the mask pattern on the silicon substrate melting at the highest incident power level tested, where the diamond-substrate mask survived. We will present here the high-power test results, along with analysis of X-ray power absorption and heat transfer in the two prototype elements, and the resulting implications for the design of the optics, beam line and heat sink for SuperKEKB.

Paper

Title

Other Keywords

Page

MOPC10

Optimization of NSLS-II Blade X-ray Beam Position Monitors: From Photoemission Type to Diamond Detector

undulator, radiation, photon, beam-position

67

P. Ilinski
BNL, Upton, Long Island, New York, USA

Optimization of blade type X-ray Beam Position Monitors (XBPM) was performed for NSLS-II undulator IVU20. Blade material, conﬁguration and operation principle were analyzed. Optimization is based on calculation of the XBPM signal spatial distribution. Along with standard photo-emission blades, Diamond Detector Blade (DDB) was examined as XBPM signal source. Analyses revealed, that Diamond Detector Blade XBPM would allow to overcome drawbacks of the photo-emission type XBPMs.

MOPC34

Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source

optics, radiation, longitudinal, storage-ring

143

W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom
R. Bartolini, P. Karataev
JAI, Oxford, United Kingdom
P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom

An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPC43

Performance of Detectors using Diamond Sensors at the LHC and CMS

beam-losses, LHC, luminosity, injection

174

M. Hempel
BTU, Cottbus, Germany
T. Baer, A.E. Dabrowski
CERN, Geneva, Switzerland
E. Griesmayer
ATI, Wien, Austria
W. Lange, O. Novgorodova
DESY Zeuthen, Zeuthen, Germany
W. Lohmann
DESY, Hamburg, Germany
N.J. Odell
NU, Evanston, USA
D.P. Stickland
PU, Princeton, New Jersey, USA

Diamond detectors are used as beam loss and luminosity monitors for CMS and LHC. A time resolution in the nanosecond range allows to detect beam losses and luminosities of single bunches. The radiation hardness and negligible temperature dependence allow the usage of diamond sensors in high radiation fields without cooling. Two different diamond detector types are installed at LHC and CMS. One is based on pCVD diamonds and installed at different locations in the LHC tunnel for beam loss monitoring. Measurements of these detectors are used to perform a bunch-by-bunch beam loss analysis. They allow to disentangle the origin of beam losses. The second type uses sCVD diamonds and is located inside CMS for van-der-Meer scan, beam halo and online luminosity monitoring and around the LHC tunnel for beam loss observation. Results on the performance of these detectors will be presented and examples of the use for analyzing the beam conditions will be given. In order to persist the enhanced requirements of the LHC after the long shutdown, e.g. higher luminosity, an upgrade of the detectors is required. The concept of the new detectors will be presented and first results will be shown.

Poster MOPC43 [0.721 MB]

MOPC45

A Prototype Readout System for the Diamond Beam Loss Monitors at LHC

beam-losses, LHC, injection, proton

182

E. Effinger, T. Baer, B. Dehning, R. Schmidt
CERN, Geneva, Switzerland
H. Frais-Kölbl
FH WN, Wiener Neustadt, Austria
E. Griesmayer
ATI, Wien, Austria
P. Kavrigin
CIVIDEC Instrumentation, Wien, Austria

Diamond Beam Loss Monitors are used at the LHC for the measurement of fast beam losses. Results from specimen LHC loss measurements are presented in this talk. The bunch-to-bunch loss measurements make full use of the fast signal response of the diamond detectors with 1 ns time resolution and 6.7 ns double pulse resolution. The data processing is done with a dedicated readout system, which was designed and optimized for particular applications with the diamond beam loss monitors. This FPGA-based system provides on-line, real-time, and dead-time-free data processing. Several examples are presented: the Time Loss Histogram with 1.6 ns binning provides beam loss measurements that are synchronized with the revolution period throughout the full operational LHC cycle. The Post Mortem Recorder with a sampling frequency of 1 GS/s allows beam-loss-based tune estimates for all bunches in parallel. Future applications and upgrades are discussed.

Poster MOPC45 [0.778 MB]

MOPF23

Quantifying Dissipated Power From Wake Field Losses in Diagnostics Structures

simulation, impedance, resonance, single-bunch

259

A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom

As a charged particle beam passes through structures, wake fields can deposit a fraction of the energy carried by the beam as characterised by the wake loss factor. Some part of the deposited energy will be emitted into the beam pipe, some part can be coupled out of signal ports and some part will be absorbed by the materials of the structures. With increasingly higher stored currents, we require a better understanding of where all the energy deposited by wake losses ends up in order to avoid damaging components. This is of particular concern for diagnostics structures as they are often designed to couple a small fraction of energy from the beam, which makes them susceptible to thermal damage due to increased localised losses. We will detail the simulation and analysis approach which we have developed to quantify power deposition within structures. As an example the analysis of a beam position monitor pickup block of the Diamond storage ring is shown.

Poster MOPF23 [0.249 MB]

TUPC10

Operation of Diamond Light Source XBPMs with Zero Bias

electron, photon, synchrotron, beam-position

376

C. Bloomer, G. Rehm
Diamond, Oxfordshire, United Kingdom

Tungsten blade X-ray Beam Position Monitors (XBPMs) have been used at Diamond Light Source since 2007, however a long-standing problem with these devices has been the growth of leakage current through the ceramic insulation within the XBPMs over time, often becoming greater than 10% of the signal current after a few years of operation. The growth of these leakage currents has been found to be exacerbated by the application of a negative bias (-70V) to the tungsten blades, a bias suggested for optimum position sensitivity. This bias is applied in order to accelerate free electrons away from the surface of the blades and to prevent cross-talk, however, we have found that the operation of the XBPMs without bias has negligible impact on our measurements. Removal of the bias has been found to prevent the growth of leakage currents over time, and can also significantly reduce the cost of our signal acquisition by removing the need for a low-current amplifier with a bias supply.

Poster TUPC10 [0.455 MB]

WEPC10

Capability Upgrade of the Diamond Transverse Multibunch Feedback

feedback, controls, transverse, FIR

682

M.G. Abbott, G. Rehm, I.S. Uzun
Diamond, Oxfordshire, United Kingdom

We describe an upgrade to the Transverse Multi-Bunch Feedback processor used at Diamond for control of multi-bunch instabilities and measurement of betatron tunes. The new system will improve both feedback and diagnostic capabilities. Bunch by bunch selectable control over feedback filters, gain and excitation will allow finer control over feedback, allowing for example the single bunch in a hybrid or camshaft fill pattern to be controlled independently from the bunch train. It will also be possible to excite all bunches at a single frequency while simultaneously sweeping the excitation for tune measurement of a few selected bunches. The single frequency excitation can be used for bunch cleaning or continuous measurement of the beta-function. A simple programmable event sequencer will provide support for up to 8 steps of programmable sweeps and changes to feedback and excitation, allowing a variety of complex and precisely timed beam characterisation experiments including grow-damp measurements in unstable conditions.

Poster WEPC10 [0.427 MB]

WEPC22

First Steps Towards a Fast Orbit Feedback at ALBA

feedback, ESRF, brilliance, simulation

727

A. Olmos, S. Blanch-Torné, Z. Martí, J. Moldes, M. Muñoz, R. Petrocelli, X. Serra-Gallifa
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
A. Gutierrez-Milla
UAB, Barcelona, Spain

An optimum performance of the ALBA facility requires a beam orbit stability on the sub-micron level up to frequencies in the 100 Hz range. The Fast Orbit FeedBack system (FOFB) is designed to achieve such a stability. After investigation of possible system architecture, a decision has been taken that exploits the available in-house hardware. This “low-cost” first stage FOFB will be an ideal test-bench to learn about beam stabilization and find possible problems and improvements on it. This report explains the current lay-out and status of the FOFB at ALBA.

Poster WEPC22 [3.107 MB]

WEPC43

Update on Beam Loss Monitoring at CTF3 for CLIC

CLIC, beam-losses, photon, quadrupole

787

L.J. Devlin, S. Mallows, C.P. Welsch, E.N. del Busto
Cockcroft Institute, Warrington, Cheshire, United Kingdom
E. Branger
Linköping University, Linköping, Sweden
L.J. Devlin, S. Mallows, C.P. Welsch, E.N. del Busto
The University of Liverpool, Liverpool, United Kingdom
E. Effinger, E.B. Holzer, S. Mallows, E.N. del Busto
CERN, Geneva, Switzerland

Funding: Work supported by STFC Cockcroft Institute Core Grant No. ST/G008248/1
The primary role of the beam loss monitoring (BLM) system for the compact linear collider (CLIC) study is to work within the machine protection system. Due to the size of the CLIC facility, a BLM that covers large distances along the beamline is highly desirable, in particular for the CLIC drive beam decelerators, which would alternatively require some ~40,000 localised monitors. Therefore, an optical fiber BLM system is currently under investigation which can cover large sections of beamline at a time. A multimode fiber has been installed along the Test Beam Line at the CLIC test facility (CTF3) where the detection principle is based on the production of Cherenkov photons within the fiber resulting from beam loss and their subsequent transport along the fiber where they are then detected at the fiber ends using silicon photomultipliers. Several additional monitors including ACEMs, PEP-II and diamond detectors have also been installed. In this contribution the first results from the BLMs are presented, comparisons of the signals from each BLM are made and the possible achievable longitudinal resolution from the fiber BLM signal considering various loss patterns is discussed.

WEPC44

Operation of Silicon, Diamond and Liquid Helium Detectors in the Range of Room Temperature to 1.9 Kelvin and After an Irradiation Dose of Several Mega Gray

proton, LHC, beam-losses, CERN

791

C. Kurfuerst, M.R. Bartosik, B. Dehning, T. Eisel, M. Sapinski
CERN, Geneva, Switzerland
V. Eremin
IOFFE, St. Petersburg, Russia

At the triplet magnets close to the interaction regions of the LHC, the current Beam Loss Monitoring system is sensitive to the debris from the collision points. For future beams with higher energy and intensity, the expected increase in luminosity and associated increase of the debris from interaction products is expected to compete with any quench-provoking beam losses from the primary proton beams. In order to distinguish between the two, it is proposed to locate the detectors as close as possible to the superconducting coil. The detectors therefore have to be located inside the cold mass of the superconducting magnets in superfluid helium at 1.9 K. Past measurements have shown that in a liquid helium chamber, diamond and silicon detectors are promising candidates for cryogenic beam loss monitors. This contribution will show the results from new high irradiation beam measurements at both room temperature and 1.9 Kelvin to reveal the radiation tolerance of these different detectors.

WEPF15

High-Power Tests at CesrTA of X-ray Optics Elements for SuperKEKB

simulation, optics, factory, LEFT

844

J.W. Flanagan, A. Arinaga, H. Fukuma, H. Ikeda
KEK, Ibaraki, Japan
A. Lyndaker, D.P. Peterson, N.T. Rider
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

X-ray beam size monitors at SuperKEKB must withstand high, sustained incident power loads. Two prototype optics elements were fabricated and tested at CesrTA, using incident X-ray power densities comparable to those expected at the SuperKEKB LER. One element was based on a silicon substrate, the other a CVD diamond substrate, with each substrate supporting a coded aperture mask pattern in gold on its surface. The diamond substrate mask showed superior performance to the silicon substrate mask, with the the mask pattern on the silicon substrate melting at the highest incident power level tested, where the diamond-substrate mask survived. We will present here the high-power test results, along with analysis of X-ray power absorption and heat transfer in the two prototype elements, and the resulting implications for the design of the optics, beam line and heat sink for SuperKEKB.