IBIC2016 - List of Authors (Welsch, C.P.)

Paper	Title	Page
MOPG48	Optimized Cryogenic Current Comparator for CERN's Low-Energy Antiproton Facilities	161
	M.F. Fernandes, D. Alves, T. Koettig, A. Lees, E. Oponowicz, J. Tan CERN, Geneva, Switzerland M.F. Fernandes, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom R. Geithner, R. Neubert, T. Stöhlker HIJ, Jena, Germany R. Geithner, R. Neubert, T. Stöhlker IOQ, Jena, Germany M. Schwickert GSI, Darmstadt, Germany C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: This project has received funding from the European Unions Seventh Framework Programme for research, technological development and demonstration under grant agreement number 289485. Non-perturbative measurement of low-intensity charged particle beams is particularly challenging for beam diagnostics due to the low amplitude of the induced electromagnetic fields. In the low-energy Antiproton Decelerator (AD) and the future Extra Low ENergy Antiproton (ELENA) rings at CERN, an absolute measurement of the beam intensity is essential to monitor operational efficiency and provide important calibration data for all AD experiments. Cryogenic Current Comparators (CCC) based on Superconducting QUantum Interference Device (SQUID) have in the past been used for the measurement of beams in the nA range, showing a very good current resolution. However these were unable to provide a measurement of short bunched beams, due to the slew-rate limitation of SQUID devices and their strong susceptibility to external perturbations. Here, we present the measurements and results obtained during 2016 with a CCC system developed for the Antiproton Decelerator, which has been optimized to overcome these earlier limitations in terms of current resolution, system stability, the ability to cope with short bunched beams, and immunity to mechanical vibrations.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG48
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MOPG54	Laser-Based Beam Diagnostics for Accelerators and Light Sources	183
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: This project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289191. The Laser Applications at Accelerators network (LA≥NET) was selected for funding within the European Union's 7th Framework Programme. During its 4 year duration the project has successfully trained 19 Fellows and organized numerous events that were open to the wider laser and accelerator communities. The network linked research into lasers and accelerators to develop advanced particle sources, new accelerating schemes, and in particular beyond state-of-the-art beam diagnostics. This contribution summarizes the research results in laser-based beam diagnostics for accelerators and light sources. It discusses the achievable resolution of laser-based velocimeters to measure the velocity of particle beams, the resolution limits of bunch shape measurements using electro-optical crystals, position resolution of laser wire scanners, and limits in energy measurements using Compton backscattering at synchrotron light sources. Finally, it also provides a summary of past and future events organized by the network and shows how an interdisciplinary research program can provide comprehensive training to a cohort of early career researchers.
	Poster MOPG54 [0.698 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG54
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MOPG58	Coherent Diffraction Radiation Imaging Methods to Measure RMS Bunch	198
	R.B. Fiorito, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.I. Clarke, A.S. Fisher SLAC, Menlo Park, California, USA A.G. Shkvarunets UMD, College Park, Maryland, USA
	The measurement of the RMS bunch length with high resolution is very important for latest generation light sources and also a key parameter for the optimization of the final beam quality in high gradient plasma accelerators. In this contribution we present progress in the development of novel single shot, RMS bunch length diagnostic techniques based on imaging the near and far fields of coherent THz diffraction radiation (CTHzDR) that is produced as a charged particle beam interacts with a solid foil or an aperture. Recent simulation results show that the profile of a THz image of the coherent point spread function (CSF) of a beam whose radius is less than the PSF, i.e. the image produced by a single electron, is sensitive to bunch length and can thus be used as a diagnostic. The advantages and disadvantages of near field and far field imaging are examined and the results of a recent high energy (20 GeV) CTHzDR experiments at SLAC/FACET are presented. Plans for experiments to further validate and compare these imaging methods for both moderate and high energy charged particle beams are also discussed.
	Poster MOPG58 [1.067 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG58
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TUPG27	Beam Diagnostics for Medical Accelerators	387
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement No 675265. The Optimization of Medical Accelerators (OMA) is the aim of a new European Training Network that has received 4 ME of funding within the Horizon 2020 Programme of the European Union. OMA joins universities, research centers and clinical facilities with industry partners to address the challenges in treatment facility design and optimization, numerical simulations for the development of advanced treatment schemes, and beam imaging and treatment monitoring. This contribution presents an overview of the network's research into beam diagnostics and imaging. This includes investigations into applying detector technologies originally developed for high energy physics experiments (such as VELO, Medipix) for medical applications; integration of prompt gamma cameras in the clinical workflow; identification of optimum detector configurations and materials for high resolution spectrometers for proton therapy and radiography; ultra-low charge beam current monitors and diagnostics for cell studies using proton beams. It also summarizes the network-wide training program consisting of Schools, Topical Workshops and Conferences that will be open to the wider medical and accelerator communities.
	Poster TUPG27 [0.388 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG27
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TUPG28	Accelerator Optimization Through Beam Diagnostics	391
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: This project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289485. A comprehensive set of beam diagnostics is key to the successful operation and optimization of essentially any accelerator. The oPAC project received 6 M€ of funding within the EU's 7th Framework Programme. This has allowed to successfully train 23 Fellows since 2011. The network joins more than 40 institutions from all around the world, including research centers, universities and private companies. One of the project's largest work packages covers research in beam diagnostics. This includes advanced instrumentation for synchrotron light sources and medical accelerators, enhanced beam loss monitoring technologies, ultra-low emittance beam size diagnostics, diagnostics for high intensity beams, as well as the development of electronics for beam position monitors. This contribution presents an overview of the research outcomes from the diagnostics work package and the demonstrated performance of each monitor. It also shows how collaborative research helps achieving beyond state-of-the-art solutions and acts as an ideal basis for researcher training. Finally, an overview of the scientific events the network has been organizing for the wider accelerator community is given.
	Poster TUPG28 [0.429 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG28
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TUPG73	Preparatory Work for a Fluorescence Based Profile Monitor for an Electron Lens	528
	S. Udrea, P. Forck GSI, Darmstadt, Germany E. Barrios Diaz, O.R. Jones, P. Magagnin, G. Schneider, R. Veness CERN, Geneva, Switzerland P. Forck, S. Udrea IAP, Frankfurt am Main, Germany V. Tzoganis, C.P. Welsch, H.D. Zhang Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Electron lenses (e-lens) have been proposed and used to mitigate several issues related to beam dynamics in high current synchrotrons. A hollow electron lens system is presently under development as part of the collimation upgrade for the high luminosity up-grade of LHC. Moreover, at GSI an electron lens system also is proposed for space charge compensation in the SIS-18 synchrotron to decrease the tune spread and allow for the high intensities at the future FAIR facility. For effective operation, a very precise alignment is necessary between the ion beam and the low energy electron beam. For the e-lens at CERN a beam diagnostics setup based on an intersecting gas sheet and the observation of beam induced fluorescence (BIF) is under development within a collaboration between CERN, Cockcroft Institute and GSI. In this paper we give an account of recent preparatory experiments performed at the Cockcroft Institute's gas curtain experimental setup with the aim to find the optimum way of distinguishing between the signals due to the low energy electron beam and the relativistic proton beam.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG73
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WEPG20	An Optical Fibre BLM System at the Australian Synchrotron Light Source	669
	M. Kastriotou, E.B. Holzer, E. Nebot Del Busto CERN, Geneva, Switzerland M.J. Boland The University of Melbourne, Melbourne, Victoria, Australia M. Kastriotou, E. Nebot Del Busto, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom M. Kastriotou, C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Increasing demands on high energy accelerators are triggering R&D into improved beam loss monitors with a high sensitivity and dynamic range and the potential to efficiently protect the machine over its entire length. Optical fibre beam loss monitors (OBLMs) are based on the detection of Cherenkov radiation from high energy charged particles. Bearing the advantage of covering more than 100m of an accelerator with only one detector and being insensitive to X-rays, OBLMs are ideal for electron machines. The Australian Synchrotron comprises an 100 MeV 15m long linac, an 130m circumference booster synchrotron and a 3 GeV, 216m circumference electron storage ring. The entire facility was successfully covered with four OBLMs. This contribution summarises a variety of measurements performed with OBLMs at the Australian Synchrotron, including beam loss measurements during the full booster and measurements of steady-state losses in the storage ring. Different photosensors, namely Silicon Photo Multipliers (SiPM) and fast Photo Multiplier Tubes (PMTs) have been used and their respective performance limits are discussed.
	Poster WEPG20 [1.831 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG20
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WEPG71	3D Density Scans of a Supersonic Gas Jet for Beam Profile Monitoring	815
	H.D. Zhang, V. Tzoganis, C.P. Welsch, W. Widmann Cockcroft Institute, Warrington, Cheshire, United Kingdom V. Tzoganis, C.P. Welsch, W. Widmann, H.D. Zhang The University of Liverpool, Liverpool, United Kingdom
	Funding: STFC Cockcroft and EU under GA 215080. A beam profile monitor based on a supersonic gas jet was successfully tested at the Cockcroft Institute. This monitor can be used for a large variety of beams over a large energy range, including high intensity/high energy beams with large destructive power which make the use of many commonly used diagnostics impossible, and beams with a short life time which require minimum interference of the diagnostics. The achievable resolution of this type of monitor depends on the jet thickness and homogeneity. Detailed knowledge of the jet density profile is hence of high importance. In this contribution we present how a moveable vacuum gauge was successfully used to investigate the 3D density distribution of the jet. We compare the experimental data to results from simulations and discuss how the findings can help further improve of the overall jet design.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG71
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WEPG80	Optical Effects in High Resolution and High Dynamic Range Beam Imaging Systems	844
	J. Wolfenden, R.B. Fiorito, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom M. Bergamaschi, R. Kieffer, T. Lefèvre, S. Mazzoni CERN, Geneva, Switzerland P. Karataev, K.O. Kruchinin JAI, Egham, Surrey, United Kingdom
	Optical systems are used to transfer light in beam diagnostics for a variety of imaging applications. The effect of the point spread function (PSF) of these optical systems on the resulting measurements is often approximated or misunderstood. It is imperative that the optical PSF is independently characterised, as this can severely impede the attainable resolution of a diagnostic measurement. A high quality laser and specially chosen optics have been used to generate an intense optical point source in order to accomplish such a characterisation. The point source was used to measure the PSFs of various electron-beam imaging systems. These systems incorporate a digital micro-mirror array, which was used to produce very high (>105) dynamic range images. The PSF was measured at each intermediary image plane of the optical system; enabling the origin of any perturbations to the PSF to be isolated and potentially mitigated. One of the characterised systems has been used for optical transition radiation (OTR) measurements of an electron beam at KEK-ATF2 (Tsukuba, Japan).
	Poster WEPG80 [1.851 MB]
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG80
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Paper

Title

Page

Optimized Cryogenic Current Comparator for CERN's Low-Energy Antiproton Facilities

161

M.F. Fernandes, D. Alves, T. Koettig, A. Lees, E. Oponowicz, J. Tan
CERN, Geneva, Switzerland
M.F. Fernandes, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
R. Geithner, R. Neubert, T. Stöhlker
HIJ, Jena, Germany
R. Geithner, R. Neubert, T. Stöhlker
IOQ, Jena, Germany
M. Schwickert
GSI, Darmstadt, Germany
C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: This project has received funding from the European Unions Seventh Framework Programme for research, technological development and demonstration under grant agreement number 289485.
Non-perturbative measurement of low-intensity charged particle beams is particularly challenging for beam diagnostics due to the low amplitude of the induced electromagnetic fields. In the low-energy Antiproton Decelerator (AD) and the future Extra Low ENergy Antiproton (ELENA) rings at CERN, an absolute measurement of the beam intensity is essential to monitor operational efficiency and provide important calibration data for all AD experiments. Cryogenic Current Comparators (CCC) based on Superconducting QUantum Interference Device (SQUID) have in the past been used for the measurement of beams in the nA range, showing a very good current resolution. However these were unable to provide a measurement of short bunched beams, due to the slew-rate limitation of SQUID devices and their strong susceptibility to external perturbations. Here, we present the measurements and results obtained during 2016 with a CCC system developed for the Antiproton Decelerator, which has been optimized to overcome these earlier limitations in terms of current resolution, system stability, the ability to cope with short bunched beams, and immunity to mechanical vibrations.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG48

Export •

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MOPG54

Laser-Based Beam Diagnostics for Accelerators and Light Sources

183

C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: This project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289191.
The Laser Applications at Accelerators network (LA≥NET) was selected for funding within the European Union's 7th Framework Programme. During its 4 year duration the project has successfully trained 19 Fellows and organized numerous events that were open to the wider laser and accelerator communities. The network linked research into lasers and accelerators to develop advanced particle sources, new accelerating schemes, and in particular beyond state-of-the-art beam diagnostics. This contribution summarizes the research results in laser-based beam diagnostics for accelerators and light sources. It discusses the achievable resolution of laser-based velocimeters to measure the velocity of particle beams, the resolution limits of bunch shape measurements using electro-optical crystals, position resolution of laser wire scanners, and limits in energy measurements using Compton backscattering at synchrotron light sources. Finally, it also provides a summary of past and future events organized by the network and shows how an interdisciplinary research program can provide comprehensive training to a cohort of early career researchers.

Poster MOPG54 [0.698 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG54

Export •

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MOPG58

Coherent Diffraction Radiation Imaging Methods to Measure RMS Bunch

198

R.B. Fiorito, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.I. Clarke, A.S. Fisher
SLAC, Menlo Park, California, USA
A.G. Shkvarunets
UMD, College Park, Maryland, USA

The measurement of the RMS bunch length with high resolution is very important for latest generation light sources and also a key parameter for the optimization of the final beam quality in high gradient plasma accelerators. In this contribution we present progress in the development of novel single shot, RMS bunch length diagnostic techniques based on imaging the near and far fields of coherent THz diffraction radiation (CTHzDR) that is produced as a charged particle beam interacts with a solid foil or an aperture. Recent simulation results show that the profile of a THz image of the coherent point spread function (CSF) of a beam whose radius is less than the PSF, i.e. the image produced by a single electron, is sensitive to bunch length and can thus be used as a diagnostic. The advantages and disadvantages of near field and far field imaging are examined and the results of a recent high energy (20 GeV) CTHzDR experiments at SLAC/FACET are presented. Plans for experiments to further validate and compare these imaging methods for both moderate and high energy charged particle beams are also discussed.

Poster MOPG58 [1.067 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG58

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TUPG27

Beam Diagnostics for Medical Accelerators

387

C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska Curie grant agreement No 675265.
The Optimization of Medical Accelerators (OMA) is the aim of a new European Training Network that has received 4 ME of funding within the Horizon 2020 Programme of the European Union. OMA joins universities, research centers and clinical facilities with industry partners to address the challenges in treatment facility design and optimization, numerical simulations for the development of advanced treatment schemes, and beam imaging and treatment monitoring. This contribution presents an overview of the network's research into beam diagnostics and imaging. This includes investigations into applying detector technologies originally developed for high energy physics experiments (such as VELO, Medipix) for medical applications; integration of prompt gamma cameras in the clinical workflow; identification of optimum detector configurations and materials for high resolution spectrometers for proton therapy and radiography; ultra-low charge beam current monitors and diagnostics for cell studies using proton beams. It also summarizes the network-wide training program consisting of Schools, Topical Workshops and Conferences that will be open to the wider medical and accelerator communities.

Poster TUPG27 [0.388 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG27

Export •

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TUPG28

Accelerator Optimization Through Beam Diagnostics

391

C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: This project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 289485.
A comprehensive set of beam diagnostics is key to the successful operation and optimization of essentially any accelerator. The oPAC project received 6 M€ of funding within the EU's 7th Framework Programme. This has allowed to successfully train 23 Fellows since 2011. The network joins more than 40 institutions from all around the world, including research centers, universities and private companies. One of the project's largest work packages covers research in beam diagnostics. This includes advanced instrumentation for synchrotron light sources and medical accelerators, enhanced beam loss monitoring technologies, ultra-low emittance beam size diagnostics, diagnostics for high intensity beams, as well as the development of electronics for beam position monitors. This contribution presents an overview of the research outcomes from the diagnostics work package and the demonstrated performance of each monitor. It also shows how collaborative research helps achieving beyond state-of-the-art solutions and acts as an ideal basis for researcher training. Finally, an overview of the scientific events the network has been organizing for the wider accelerator community is given.

Poster TUPG28 [0.429 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG28

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPG73

Preparatory Work for a Fluorescence Based Profile Monitor for an Electron Lens

528

S. Udrea, P. Forck
GSI, Darmstadt, Germany
E. Barrios Diaz, O.R. Jones, P. Magagnin, G. Schneider, R. Veness
CERN, Geneva, Switzerland
P. Forck, S. Udrea
IAP, Frankfurt am Main, Germany
V. Tzoganis, C.P. Welsch, H.D. Zhang
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Electron lenses (e-lens) have been proposed and used to mitigate several issues related to beam dynamics in high current synchrotrons. A hollow electron lens system is presently under development as part of the collimation upgrade for the high luminosity up-grade of LHC. Moreover, at GSI an electron lens system also is proposed for space charge compensation in the SIS-18 synchrotron to decrease the tune spread and allow for the high intensities at the future FAIR facility. For effective operation, a very precise alignment is necessary between the ion beam and the low energy electron beam. For the e-lens at CERN a beam diagnostics setup based on an intersecting gas sheet and the observation of beam induced fluorescence (BIF) is under development within a collaboration between CERN, Cockcroft Institute and GSI. In this paper we give an account of recent preparatory experiments performed at the Cockcroft Institute's gas curtain experimental setup with the aim to find the optimum way of distinguishing between the signals due to the low energy electron beam and the relativistic proton beam.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG73

Export •

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WEPG20

An Optical Fibre BLM System at the Australian Synchrotron Light Source

669

M. Kastriotou, E.B. Holzer, E. Nebot Del Busto
CERN, Geneva, Switzerland
M.J. Boland
The University of Melbourne, Melbourne, Victoria, Australia
M. Kastriotou, E. Nebot Del Busto, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
M. Kastriotou, C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Increasing demands on high energy accelerators are triggering R&D into improved beam loss monitors with a high sensitivity and dynamic range and the potential to efficiently protect the machine over its entire length. Optical fibre beam loss monitors (OBLMs) are based on the detection of Cherenkov radiation from high energy charged particles. Bearing the advantage of covering more than 100m of an accelerator with only one detector and being insensitive to X-rays, OBLMs are ideal for electron machines. The Australian Synchrotron comprises an 100 MeV 15m long linac, an 130m circumference booster synchrotron and a 3 GeV, 216m circumference electron storage ring. The entire facility was successfully covered with four OBLMs. This contribution summarises a variety of measurements performed with OBLMs at the Australian Synchrotron, including beam loss measurements during the full booster and measurements of steady-state losses in the storage ring. Different photosensors, namely Silicon Photo Multipliers (SiPM) and fast Photo Multiplier Tubes (PMTs) have been used and their respective performance limits are discussed.

Poster WEPG20 [1.831 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG20

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WEPG71

3D Density Scans of a Supersonic Gas Jet for Beam Profile Monitoring

815

H.D. Zhang, V. Tzoganis, C.P. Welsch, W. Widmann
Cockcroft Institute, Warrington, Cheshire, United Kingdom
V. Tzoganis, C.P. Welsch, W. Widmann, H.D. Zhang
The University of Liverpool, Liverpool, United Kingdom

Funding: STFC Cockcroft and EU under GA 215080.
A beam profile monitor based on a supersonic gas jet was successfully tested at the Cockcroft Institute. This monitor can be used for a large variety of beams over a large energy range, including high intensity/high energy beams with large destructive power which make the use of many commonly used diagnostics impossible, and beams with a short life time which require minimum interference of the diagnostics. The achievable resolution of this type of monitor depends on the jet thickness and homogeneity. Detailed knowledge of the jet density profile is hence of high importance. In this contribution we present how a moveable vacuum gauge was successfully used to investigate the 3D density distribution of the jet. We compare the experimental data to results from simulations and discuss how the findings can help further improve of the overall jet design.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG71

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPG80

Optical Effects in High Resolution and High Dynamic Range Beam Imaging Systems

844

J. Wolfenden, R.B. Fiorito, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom
M. Bergamaschi, R. Kieffer, T. Lefèvre, S. Mazzoni
CERN, Geneva, Switzerland
P. Karataev, K.O. Kruchinin
JAI, Egham, Surrey, United Kingdom

Optical systems are used to transfer light in beam diagnostics for a variety of imaging applications. The effect of the point spread function (PSF) of these optical systems on the resulting measurements is often approximated or misunderstood. It is imperative that the optical PSF is independently characterised, as this can severely impede the attainable resolution of a diagnostic measurement. A high quality laser and specially chosen optics have been used to generate an intense optical point source in order to accomplish such a characterisation. The point source was used to measure the PSFs of various electron-beam imaging systems. These systems incorporate a digital micro-mirror array, which was used to produce very high (>105) dynamic range images. The PSF was measured at each intermediary image plane of the optical system; enabling the origin of any perturbations to the PSF to be isolated and potentially mitigated. One of the characterised systems has been used for optical transition radiation (OTR) measurements of an electron beam at KEK-ATF2 (Tsukuba, Japan).

Poster WEPG80 [1.851 MB]

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG80

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)