IBIC2013 - List of Keywords (proton)

Paper	Title	Other Keywords	Page
MOPC13	Design of Cold Beam Position Monitor for CADS Injector II Proton LINAC	BPM, linac, cryogenics, alignment	75
	Y. Zhang, X.C. Kang, M. Li, J.X. Wu, G. Zhu IMP, Lanzhou, People's Republic of China
	Cold beam position monitor based on capacitive buttons are designed for Chinese Accelerator Driven System (CADS) Injector II proton LINAC. This LINAC is aiming to produce a maximum design current of 15 mA at the 10 MeV energy with an operating frequency of 162.5 MHz. Cold button BPM will be installed in the Cryomodule, which will be in the middle of the superconductor cavity and the superconductor magnet. Some special issues must be considered when designing a cold BPM: low-beta beam in the cryogenic environment, strong rf-field from the superconductor cavity and high magnetic field from the superconductor magnet. In this contribution, the status of cold BPM will be presented, focusing on the electromagnetic response for low-beta beams and mechanical design in the cryogenic environment.

MOPC18	Development of a High Dynamic Range Beam Position Measurement System Using Logarithmic Amplifiers for the SPS at CERN	SPS, injection, beam-position, CERN	89
	J.L. Gonzalez, T.B. Bogey, C. Deplano, J.-J. Savioz CERN, Geneva, Switzerland
	A new Front-End electronics, based on Logarithmic Amplifiers, is currently being developed for the CERN SPS Multi Orbit POsition System (MOPOS). The aim is to resolve the multi-batch structure of the beams and cope with their large intensity range (> 70 dB). Position and intensity signals are digitized in the Front-End electronics installed in the tunnel. The data are then transmitted over a serial fibre-optic link to a VME Digital Acquisition board located in surface buildings. A first prototype, equipped with a calibration system, has been successfully tested on the SPS under different beam conditions, including single bunch, 25ns and 50ns bunch trains. The system architecture and the first beam measurements are reported in this paper.
	Poster MOPC18 [4.013 MB]

MOPC21	Layout of the BPM System for p-LINAC at FAIR and the Digital Methods for Beam Position and Phase Monitoring	BPM, beam-position, linac, single-bunch	101
	M.H. Almalki, G. Clemente, P. Forck, L. Groening, W. Kaufmann, P. Kowina, C. Krüger, R. Singh GSI, Darmstadt, Germany W. Ackermann TEMF, TU Darmstadt, Darmstadt, Germany M.H. Almalki IAP, Frankfurt am Main, Germany M.H. Almalki KACST, Riyadh, Kingdom of Saudi Arabia B.B. Baricevic, R. Hrovatin, P.L. Lemut, M. Znidarcic I-Tech, Solkan, Slovenia C.S. Simon CEA/DSM/IRFU, France
	The planned Proton LINAC at the FAIR facility will provide a beam current from 35 to 70 mA accelerated to 70 MeV by novel CH-type DTLs. Four-fold button Beam Position Monitor (BPM) will be installed at 14 locations along the LINAC and some of these BPMs are mounted only about 40 mm upstream of the CH cavities. The coupling of the RF accelerating field to the BPMs installed close to the CH cavities was numerically investigated. For the digital signal processing using I/Q demodulation a 'Libera Single Pass H' is foreseen. The properties of this digitization and processing scheme were characterized by detailed lab-based tests. Moreover, the performance was investigated by a 80 μA Ne⁴⁺ beam at 1.4 MeV / u and compared to a time-domain approach and successive FFT calculation. In particular, concerning the phase determination significant deviations between the methods were observed and further investigations to understand the reason are ongoing.
	Poster MOPC21 [1.622 MB]

MOPC45	A Prototype Readout System for the Diamond Beam Loss Monitors at LHC	beam-losses, DIAMOND, LHC, injection	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]

MOPF07	Turn by Turn Profile Monitors for the CERN SPS and LHC	LHC, OTR, SPS, optics	216
	S. Burger, A. Boccardi, E. Bravin, A. Goldblatt, A. Ravni, F. Roncarolo, R.S. Sautier CERN, Geneva, Switzerland
	In order to preserve the transverse beam emittance along the acceleration chain it is important that the optics of the transfer lines is perfectly matched to the optics of the rings. Special monitors capable of measuring the beam profiles with a turn by turn resolution are very helpful in this respect. A new type of matching monitor has been developed at CERN for the SPS and LHC machines. This monitor relies on imaging OTR light by mean of a fast line scan CMOS and an asymmetric optical system based on cylindrical lenses. This contribution describes the design of this monitor, presents the results obtained during the 2012-13 run and outlines the plans for further improving the design.

MOPF15	Advanced uses of a Current Transformer and a Multi-Wire Profile Monitor for Online Monitoring of the Stripper Foil Degradation in the 3-GeV RCS of J-PARC	injection, monitoring, target, linac	239
	P.K. Saha, H. Harada, S. Hatakeyama, N. Hayashi, H. Hotchi, M. Kinsho, K. Okabe, R. Saeki, K. Yamamoto, Y. Yamazaki, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	We have established advanced and sophisticated uses of a Current Transformer (CT) and a Multi-Wire Profile Monitor (MWPM) for measuring as well as online monitoring of the stripper foil degradation during user operation of the 3-GeV Rapid Cycling Synchrotron (RCS) in Japan Proton Accelerator Research Complex (J-PARC). An incoming negative hydrogen beam from the Linac is stripped to a proton beam by using a stripper foil placed in the RCS injection area. Foil degradation such as, foil thinning and pinhole formation are believed to be signs of a foil breaking. A sudden foil breaking is not only a load on the accelerator downtime but also raises maintenance issues. In a high intensity accelerator like RCS, a proper monitoring system of the foil is thus important in order to avoid such above issues by replacing the foil with a new one in the scheduled maintenance day. The thickness of the stipper foil used for the present 181 MeV injection energy is 200 ug/cm², where a change of foil thickness as low as 1% or even less has already been successfully monitored by utilizing the presented method. Measured data for the last 6 months operation of the RCS will be presented.
	Poster MOPF15 [1.591 MB]

MOPF29	A Non-Invasive Beam Monitor for Hadron Therapy Beams	CERN, target, LHC, vacuum	283
	T. Cybulski, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom T. Cybulski, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom A. Kacperek, B. Marsland, I. Taylor, A. Wray The Douglas Cyclotron, The Clatterbridge Cancer Centre NHS Foundation Trust, Wirral, United Kingdom
	Funding: Work supported by the EU under contract PITN-GA-2008-215080 and the STFC Cockcroft Institute Core Grant No. ST/G008248/1 Hadron therapy allows for precise dose delivery to the tumour volume only and hence decreases the dose delivered to the nearby organs and healthy tissue. Ideally, the beam would be monitored whilst being delivered to the patient. A novel, real–time and non-interceptive beam monitor for hadron therapy beams has been developed in the QUASAR Group. It is based on the LHCb VErtex LOcator (VELO) detector and couples to the treatment beam’s transverse halo to determine the intensity, position and ultimately the dose of the treatment beam. This contribution presents the design of a stand-alone version of the VELO detector which was developed for the Clatterbridge Cancer Centre (CCC) treatment line. The mechanical and electronic design of the monitor and its data acquisition system are shown, with a focus on the detector positioning and cooling system. Monte Carlo simulations into expected signal distributions are compared against first measurements with the 60 MeV proton beam at CCC.

TUPC39	Dispersive Fourier-Transform Electrooptical Sampling for Single-Shot Modulation Measurement in a Proton-Driven Plasma Wakefield Accelerator	plasma, laser, radiation, transverse	467
	O. Reimann MPI-P, München, Germany R. Tarkeshian MPI, Muenchen, Germany
	The concept of proton-driven plasma wakefield acceleration has recently been proposed as a means of accelerating a bunch of electrons to high energies with very high gradients, and a demonstration experiment (AWAKE) at CERN is now under development. For this a clear understanding of the temporal and spatial modulation of the proton driver bunches after propagating the plasma channel is essential. A single-shot electrooptical sampling system using dispersive Fourier-transform exploiting transverse coherent transition radiation* is proposed here to determine the bunch modulation and field properties in the frequency domain. Frequencies up to the terahertz region with a resolution of less than 10 GHz are measurable. The system with a closed optical fiber path is based on a semiconductor laser source to achieve easy handling and robustness. The principle idea, estimations of the required sensitivity, and first experimental results are presented. * Pukhov, A. et al. Phys. Rev.ST Accel. Beams 15 (2012)

TUPC47	Simulation for Radiation Field Caused by Beam Loss of C-ADS Injector II	photon, beam-losses, electron, radiation	489
	G. Ren, W. Li, Y. Li USTC/NSRL, Hefei, Anhui, People's Republic of China M. Zeng Tsinghua University, Beijing, People's Republic of China
	CADS is a Chinese ADS(Accelerator Driven Sub-critical System) project. Its injector is a high current, full superconducting proton accelerator. For such a facility, a BLM system is necessary, especially in low energy segments. This paper presents some basic simulation for 10MeV proton by Monte Carlo program FLUKA, as well as the distributions we got about different secondary particles in three aspects: angular, energy spectrum and current. These results are helpful to select the detector type and its location, determine its dynamic range matching different requirements for both fast and slow beam loss. This paper also analyzes the major impact of the background, such as superconducting cavity X radiation and radiation caused by material activation. This work is meaningful in BLM system research.

TUPF16	Analysis of Measurement Errors of INR Linac Ionization Beam Cross Section Monitor	ion, linac, space-charge, simulation	535
	S.A. Gavrilov, A. Feschenko, P.I. Reinhardt-Nickoulin, I.V. Vasilyev RAS/INR, Moscow, Russia A. Feschenko, S.A. Gavrilov MIPT, Dolgoprudniy, Moscow Region, Russia
	Residual gas ionization beam cross section monitors (BCSM) are installed at LEBT and HEBT of INR RAS proton linac to measure cross section, profiles and position of the beam. BCSMs provide two-dimensional non-destructive real-time beam diagnostics at LINAC operation with repetition frequency from 1 to 50 Hz, pulses duration from 0.3 to 170 μs and wide range of amplitudes, particle energy 400 keV and 209 MeV. The analysis of systematic measurements errors (accuracy) because of nonuniform electrostatic fields, determined by BCSM design features, is presented. New detector model, minimizing these nonuniformities, is shown. Besides that, the analysis of statistical errors (precision) due to the method features, in particular, ions thermal motion and a beam space charge, is done. The simulation results make it possible to estimate measured cross sections size, profiles and beam positions and to draw conclusions about the reliability of BCSM results for beams with various parameters.

WECL3	The LUPIN Detector: Supporting Least Intrusive Beam Monitoring Technique Through Neutron Detection	radiation, beam-losses, monitoring, synchrotron	648
	G.P. Manessi, M. Silari CERN, Geneva, Switzerland M. Caresana Politecnico/Milano, Milano, Italy M. Ferrarini CNAO Foundation, Milan, Italy G.P. Manessi, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom G.P. Manessi, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	The Long interval, Ultra-wide dynamic Pile-up free Neutron rem counter (LUPIN) is a novel detector initially developed for radiation protection purposes, specifically conceived for applications in pulsed neutron fields. The detector has a measurement capability varying over many orders of neutron burst intensity, from a single neutron up to thousands of interactions for each burst, without showing any saturation effect. Whilst LUPIN has been developed for applications in the radiation protection fields, its unique properties make it also well suited to support other beam instrumentation. In this contribution, the design of LUPIN is presented in detail and its main characteristics are summarized. Its potential use as beam loss monitor and complementary detector for non-invasive beam monitoring purposes (e.g. to complement a monitor based on proton beam “halo” detection) in medical accelerators is then examined. In the context of its application as a beam loss monitor for hadrontherapy accelerators, results of measurements performed at the Italian National Centre of Hadrontherapy (CNAO) are presented and analyzed.
	Slides WECL3 [1.431 MB]

WEPC05	The ELENA Beam Diagnostics Systems	antiproton, electron, pick-up, CERN	664
	G. Tranquille CERN, Geneva, Switzerland
	The Extra Low ENergy Antiproton ring (ELENA) to be built at CERN is aimed at substantially increasing the number of antiprotons to the low energy antiproton physics community. It will be a small machine which will decelerate low intensity beams (<4x10⁷) from 5.3 MeV to 100 keV and will be equipped with an electron cooler to avoid beam losses during the deceleration and to significantly reduce beam phase space at extraction. To measure the beam parameters from the extraction point of the Antiproton Decelerator (AD), through the ELENA ring and all the way to the experiments, many systems will be needed to ensure that the desired beam characteristics are obtained. Particular attention needs to be paid to the performance of the electron cooler which depends on reliable instrumentation in order to efficiently cool the antiprotons. This contribution will present the different monitors that have been proposed to measure the various beam parameters as well as some of the developments going on to further improve the ELENA diagnostics.
	Poster WEPC05 [1.767 MB]

WEPC25	Optimisation of a Split Plate Position Monitor for the ISIS Proton Synchrotron	beam-position, coupling, BPM, simulation	739
	C.C. Wilcox, J.C. Medland, S.J. Payne, A. Pertica, M.A. Probert STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	A new Beam Position Monitor (BPM) has been designed for the ISIS proton accelerator facility at the Rutherford Appleton Laboratory in the UK. The new monitor, which will be installed in the beam line to Target 1, is of a ‘split plate’ design which utilises two pairs of electrodes to allow the beam position to be measured simultaneously in the horizontal and vertical planes. Simulations carried out using the CST low frequency solver have highlighted the inaccuracies in the measured beam position caused by strong inter-electrode coupling in such a monitor. This coupling, along with imbalanced electrode capacitances, leads to reduced sensitivity to changes in beam position as well as producing a positional offset error. This paper describes how the problems associated with inter-electrode coupling have been removed with the addition of grounded rings placed between each of the four electrodes. The design and positioning of the rings also ensured that the four electrode capacitances were matched. The results are presented both as CST simulations of ‘thin wire’ beam position measurements and results from bench measurements of a prototype dual plane BPM.

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	DIAMOND, 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.

WEPF10	Wire Scanner Design for the European Spallation Source	linac, ESS, CERN, diagnostics	830
	B. Cheymol, A. Jansson, T.J. Shea ESS, Lund, Sweden
	The European Spallation Source (ESS), to be built in the south of Sweden, will use a 2 GeV superconducting LINAC to produce the world's most powerful neutron source with a beam power of 5 MW. The beam power is a challenge for interceptive beam diagnostics like wire scanner, the thermal load on intercepting devices implies to reduce the beam power in order to preserve the device integrity. For nominal operation, non-disturbing techniques for profile measurements are planned, while for the commissioning phase, accurate measurements and cross checking, wire scanners will be used. This paper describes the preliminary design of the wire scanner system in the normal conducing LINAC as well as in the superconducting LINAC.

Paper

Title

Other Keywords

Page

MOPC13

Design of Cold Beam Position Monitor for CADS Injector II Proton LINAC

BPM, linac, cryogenics, alignment

75

Y. Zhang, X.C. Kang, M. Li, J.X. Wu, G. Zhu
IMP, Lanzhou, People's Republic of China

Cold beam position monitor based on capacitive buttons are designed for Chinese Accelerator Driven System (CADS) Injector II proton LINAC. This LINAC is aiming to produce a maximum design current of 15 mA at the 10 MeV energy with an operating frequency of 162.5 MHz. Cold button BPM will be installed in the Cryomodule, which will be in the middle of the superconductor cavity and the superconductor magnet. Some special issues must be considered when designing a cold BPM: low-beta beam in the cryogenic environment, strong rf-field from the superconductor cavity and high magnetic field from the superconductor magnet. In this contribution, the status of cold BPM will be presented, focusing on the electromagnetic response for low-beta beams and mechanical design in the cryogenic environment.

MOPC18

Development of a High Dynamic Range Beam Position Measurement System Using Logarithmic Amplifiers for the SPS at CERN

SPS, injection, beam-position, CERN

89

J.L. Gonzalez, T.B. Bogey, C. Deplano, J.-J. Savioz
CERN, Geneva, Switzerland

A new Front-End electronics, based on Logarithmic Amplifiers, is currently being developed for the CERN SPS Multi Orbit POsition System (MOPOS). The aim is to resolve the multi-batch structure of the beams and cope with their large intensity range (> 70 dB). Position and intensity signals are digitized in the Front-End electronics installed in the tunnel. The data are then transmitted over a serial fibre-optic link to a VME Digital Acquisition board located in surface buildings. A first prototype, equipped with a calibration system, has been successfully tested on the SPS under different beam conditions, including single bunch, 25ns and 50ns bunch trains. The system architecture and the first beam measurements are reported in this paper.

Poster MOPC18 [4.013 MB]

MOPC21

Layout of the BPM System for p-LINAC at FAIR and the Digital Methods for Beam Position and Phase Monitoring

BPM, beam-position, linac, single-bunch

101

M.H. Almalki, G. Clemente, P. Forck, L. Groening, W. Kaufmann, P. Kowina, C. Krüger, R. Singh
GSI, Darmstadt, Germany
W. Ackermann
TEMF, TU Darmstadt, Darmstadt, Germany
M.H. Almalki
IAP, Frankfurt am Main, Germany
M.H. Almalki
KACST, Riyadh, Kingdom of Saudi Arabia
B.B. Baricevic, R. Hrovatin, P.L. Lemut, M. Znidarcic
I-Tech, Solkan, Slovenia
C.S. Simon
CEA/DSM/IRFU, France

The planned Proton LINAC at the FAIR facility will provide a beam current from 35 to 70 mA accelerated to 70 MeV by novel CH-type DTLs. Four-fold button Beam Position Monitor (BPM) will be installed at 14 locations along the LINAC and some of these BPMs are mounted only about 40 mm upstream of the CH cavities. The coupling of the RF accelerating field to the BPMs installed close to the CH cavities was numerically investigated. For the digital signal processing using I/Q demodulation a 'Libera Single Pass H' is foreseen. The properties of this digitization and processing scheme were characterized by detailed lab-based tests. Moreover, the performance was investigated by a 80 μA Ne⁴⁺ beam at 1.4 MeV / u and compared to a time-domain approach and successive FFT calculation. In particular, concerning the phase determination significant deviations between the methods were observed and further investigations to understand the reason are ongoing.

Poster MOPC21 [1.622 MB]

MOPC45

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

beam-losses, DIAMOND, LHC, injection

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]

MOPF07

Turn by Turn Profile Monitors for the CERN SPS and LHC

LHC, OTR, SPS, optics

216

S. Burger, A. Boccardi, E. Bravin, A. Goldblatt, A. Ravni, F. Roncarolo, R.S. Sautier
CERN, Geneva, Switzerland

In order to preserve the transverse beam emittance along the acceleration chain it is important that the optics of the transfer lines is perfectly matched to the optics of the rings. Special monitors capable of measuring the beam profiles with a turn by turn resolution are very helpful in this respect. A new type of matching monitor has been developed at CERN for the SPS and LHC machines. This monitor relies on imaging OTR light by mean of a fast line scan CMOS and an asymmetric optical system based on cylindrical lenses. This contribution describes the design of this monitor, presents the results obtained during the 2012-13 run and outlines the plans for further improving the design.

MOPF15

Advanced uses of a Current Transformer and a Multi-Wire Profile Monitor for Online Monitoring of the Stripper Foil Degradation in the 3-GeV RCS of J-PARC

injection, monitoring, target, linac

239

P.K. Saha, H. Harada, S. Hatakeyama, N. Hayashi, H. Hotchi, M. Kinsho, K. Okabe, R. Saeki, K. Yamamoto, Y. Yamazaki, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

We have established advanced and sophisticated uses of a Current Transformer (CT) and a Multi-Wire Profile Monitor (MWPM) for measuring as well as online monitoring of the stripper foil degradation during user operation of the 3-GeV Rapid Cycling Synchrotron (RCS) in Japan Proton Accelerator Research Complex (J-PARC). An incoming negative hydrogen beam from the Linac is stripped to a proton beam by using a stripper foil placed in the RCS injection area. Foil degradation such as, foil thinning and pinhole formation are believed to be signs of a foil breaking. A sudden foil breaking is not only a load on the accelerator downtime but also raises maintenance issues. In a high intensity accelerator like RCS, a proper monitoring system of the foil is thus important in order to avoid such above issues by replacing the foil with a new one in the scheduled maintenance day. The thickness of the stipper foil used for the present 181 MeV injection energy is 200 ug/cm², where a change of foil thickness as low as 1% or even less has already been successfully monitored by utilizing the presented method. Measured data for the last 6 months operation of the RCS will be presented.

Poster MOPF15 [1.591 MB]

MOPF29

A Non-Invasive Beam Monitor for Hadron Therapy Beams

CERN, target, LHC, vacuum

283

T. Cybulski, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
T. Cybulski, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
A. Kacperek, B. Marsland, I. Taylor, A. Wray
The Douglas Cyclotron, The Clatterbridge Cancer Centre NHS Foundation Trust, Wirral, United Kingdom

Funding: Work supported by the EU under contract PITN-GA-2008-215080 and the STFC Cockcroft Institute Core Grant No. ST/G008248/1
Hadron therapy allows for precise dose delivery to the tumour volume only and hence decreases the dose delivered to the nearby organs and healthy tissue. Ideally, the beam would be monitored whilst being delivered to the patient. A novel, real–time and non-interceptive beam monitor for hadron therapy beams has been developed in the QUASAR Group. It is based on the LHCb VErtex LOcator (VELO) detector and couples to the treatment beam’s transverse halo to determine the intensity, position and ultimately the dose of the treatment beam. This contribution presents the design of a stand-alone version of the VELO detector which was developed for the Clatterbridge Cancer Centre (CCC) treatment line. The mechanical and electronic design of the monitor and its data acquisition system are shown, with a focus on the detector positioning and cooling system. Monte Carlo simulations into expected signal distributions are compared against first measurements with the 60 MeV proton beam at CCC.

TUPC39

Dispersive Fourier-Transform Electrooptical Sampling for Single-Shot Modulation Measurement in a Proton-Driven Plasma Wakefield Accelerator

plasma, laser, radiation, transverse

467

O. Reimann
MPI-P, München, Germany
R. Tarkeshian
MPI, Muenchen, Germany

The concept of proton-driven plasma wakefield acceleration has recently been proposed as a means of accelerating a bunch of electrons to high energies with very high gradients, and a demonstration experiment (AWAKE) at CERN is now under development. For this a clear understanding of the temporal and spatial modulation of the proton driver bunches after propagating the plasma channel is essential. A single-shot electrooptical sampling system using dispersive Fourier-transform exploiting transverse coherent transition radiation* is proposed here to determine the bunch modulation and field properties in the frequency domain. Frequencies up to the terahertz region with a resolution of less than 10 GHz are measurable. The system with a closed optical fiber path is based on a semiconductor laser source to achieve easy handling and robustness. The principle idea, estimations of the required sensitivity, and first experimental results are presented.
* Pukhov, A. et al. Phys. Rev.ST Accel. Beams 15 (2012)

TUPC47

Simulation for Radiation Field Caused by Beam Loss of C-ADS Injector II

photon, beam-losses, electron, radiation

489

G. Ren, W. Li, Y. Li
USTC/NSRL, Hefei, Anhui, People's Republic of China
M. Zeng
Tsinghua University, Beijing, People's Republic of China

CADS is a Chinese ADS(Accelerator Driven Sub-critical System) project. Its injector is a high current, full superconducting proton accelerator. For such a facility, a BLM system is necessary, especially in low energy segments. This paper presents some basic simulation for 10MeV proton by Monte Carlo program FLUKA, as well as the distributions we got about different secondary particles in three aspects: angular, energy spectrum and current. These results are helpful to select the detector type and its location, determine its dynamic range matching different requirements for both fast and slow beam loss. This paper also analyzes the major impact of the background, such as superconducting cavity X radiation and radiation caused by material activation. This work is meaningful in BLM system research.

TUPF16

Analysis of Measurement Errors of INR Linac Ionization Beam Cross Section Monitor

ion, linac, space-charge, simulation

535

S.A. Gavrilov, A. Feschenko, P.I. Reinhardt-Nickoulin, I.V. Vasilyev
RAS/INR, Moscow, Russia
A. Feschenko, S.A. Gavrilov
MIPT, Dolgoprudniy, Moscow Region, Russia

Residual gas ionization beam cross section monitors (BCSM) are installed at LEBT and HEBT of INR RAS proton linac to measure cross section, profiles and position of the beam. BCSMs provide two-dimensional non-destructive real-time beam diagnostics at LINAC operation with repetition frequency from 1 to 50 Hz, pulses duration from 0.3 to 170 μs and wide range of amplitudes, particle energy 400 keV and 209 MeV. The analysis of systematic measurements errors (accuracy) because of nonuniform electrostatic fields, determined by BCSM design features, is presented. New detector model, minimizing these nonuniformities, is shown. Besides that, the analysis of statistical errors (precision) due to the method features, in particular, ions thermal motion and a beam space charge, is done. The simulation results make it possible to estimate measured cross sections size, profiles and beam positions and to draw conclusions about the reliability of BCSM results for beams with various parameters.

WECL3

The LUPIN Detector: Supporting Least Intrusive Beam Monitoring Technique Through Neutron Detection

radiation, beam-losses, monitoring, synchrotron

648

G.P. Manessi, M. Silari
CERN, Geneva, Switzerland
M. Caresana
Politecnico/Milano, Milano, Italy
M. Ferrarini
CNAO Foundation, Milan, Italy
G.P. Manessi, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
G.P. Manessi, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

The Long interval, Ultra-wide dynamic Pile-up free Neutron rem counter (LUPIN) is a novel detector initially developed for radiation protection purposes, specifically conceived for applications in pulsed neutron fields. The detector has a measurement capability varying over many orders of neutron burst intensity, from a single neutron up to thousands of interactions for each burst, without showing any saturation effect. Whilst LUPIN has been developed for applications in the radiation protection fields, its unique properties make it also well suited to support other beam instrumentation. In this contribution, the design of LUPIN is presented in detail and its main characteristics are summarized. Its potential use as beam loss monitor and complementary detector for non-invasive beam monitoring purposes (e.g. to complement a monitor based on proton beam “halo” detection) in medical accelerators is then examined. In the context of its application as a beam loss monitor for hadrontherapy accelerators, results of measurements performed at the Italian National Centre of Hadrontherapy (CNAO) are presented and analyzed.

Slides WECL3 [1.431 MB]

WEPC05

The ELENA Beam Diagnostics Systems

antiproton, electron, pick-up, CERN

664

G. Tranquille
CERN, Geneva, Switzerland

The Extra Low ENergy Antiproton ring (ELENA) to be built at CERN is aimed at substantially increasing the number of antiprotons to the low energy antiproton physics community. It will be a small machine which will decelerate low intensity beams (<4x10⁷) from 5.3 MeV to 100 keV and will be equipped with an electron cooler to avoid beam losses during the deceleration and to significantly reduce beam phase space at extraction. To measure the beam parameters from the extraction point of the Antiproton Decelerator (AD), through the ELENA ring and all the way to the experiments, many systems will be needed to ensure that the desired beam characteristics are obtained. Particular attention needs to be paid to the performance of the electron cooler which depends on reliable instrumentation in order to efficiently cool the antiprotons. This contribution will present the different monitors that have been proposed to measure the various beam parameters as well as some of the developments going on to further improve the ELENA diagnostics.

Poster WEPC05 [1.767 MB]

WEPC25

Optimisation of a Split Plate Position Monitor for the ISIS Proton Synchrotron

beam-position, coupling, BPM, simulation

739

C.C. Wilcox, J.C. Medland, S.J. Payne, A. Pertica, M.A. Probert
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

A new Beam Position Monitor (BPM) has been designed for the ISIS proton accelerator facility at the Rutherford Appleton Laboratory in the UK. The new monitor, which will be installed in the beam line to Target 1, is of a ‘split plate’ design which utilises two pairs of electrodes to allow the beam position to be measured simultaneously in the horizontal and vertical planes. Simulations carried out using the CST low frequency solver have highlighted the inaccuracies in the measured beam position caused by strong inter-electrode coupling in such a monitor. This coupling, along with imbalanced electrode capacitances, leads to reduced sensitivity to changes in beam position as well as producing a positional offset error. This paper describes how the problems associated with inter-electrode coupling have been removed with the addition of grounded rings placed between each of the four electrodes. The design and positioning of the rings also ensured that the four electrode capacitances were matched. The results are presented both as CST simulations of ‘thin wire’ beam position measurements and results from bench measurements of a prototype dual plane BPM.

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

DIAMOND, 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.

WEPF10

Wire Scanner Design for the European Spallation Source

linac, ESS, CERN, diagnostics

830

B. Cheymol, A. Jansson, T.J. Shea
ESS, Lund, Sweden

The European Spallation Source (ESS), to be built in the south of Sweden, will use a 2 GeV superconducting LINAC to produce the world's most powerful neutron source with a beam power of 5 MW. The beam power is a challenge for interceptive beam diagnostics like wire scanner, the thermal load on intercepting devices implies to reduce the beam power in order to preserve the device integrity. For nominal operation, non-disturbing techniques for profile measurements are planned, while for the commissioning phase, accurate measurements and cross checking, wire scanners will be used. This paper describes the preliminary design of the wire scanner system in the normal conducing LINAC as well as in the superconducting LINAC.