IBIC2014 - List of Keywords (target)

Paper	Title	Other Keywords	Page
MOPF14	Vertical Beam Size Measurement at CesrTA Using Diffraction Radiation	radiation, electron, background, polarization	77
	L.M. Bobb, T. Aumeyr, P. Karataev JAI, Egham, Surrey, United Kingdom T. Aumeyr, P. Karataev Royal Holloway, University of London, Surrey, United Kingdom M.G. Billing, J.V. Conway Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA L.M. Bobb DLS, Oxfordshire, United Kingdom E. Bravin, T. Lefèvre, S. Mazzoni, H. Schmickler CERN, Geneva, Switzerland
	Over recent years the first Diffraction Radiation (DR) beam size monitor has been tested on a circular machine. At CesrTA, Cornell University, USA, the sensitivity and limitations of the DR monitor for vertical beam size measurement has been investigated. DR emitted from 1 and 0.5 mm target apertures was observed at 400 and 600 nm wavelengths. In addition, interference between the DR signals emitted by the target and mask has been observed. In this report, we present the recent observations and discuss areas for improvement.
	Poster MOPF14 [3.379 MB]
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MOPF28	Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac	linac, timing, electron, positron	110
	F. Miyahara, K. Furukawa, R. Ichimiya, N. Iida, M. Ikeno, H. Kaji, M. Satoh, M. Shoji, T. Suwada, M. Tanaka, Y. Yano KEK, Ibaraki, Japan T. Okazaki EJIT, Hitachi, Ibaraki, Japan
	The SuperKEKB injector linac has multiple operation modes for the electron beam injection into 3 separate rings, SuperKEKB HER, PF (Photon Factory) Ring and PF-AR, and the positron beam injection into the damping ring and the SuperKEKB LER. The operation modes can be switched every 20 milli-second with arbitrary order. The beam parameters such as charge, energy and emittance are different for each of the rings. Moreover, the bunch charge of the electron beam, 5nC, is 5 times higher and the emittance of ~10 mm•mrad is 30 times lower than those of the KEKB injector. Thus, development of BPM readout system with a wide dynamic range and installation of optical fiber detector with a good S/N ratio for the wire scanners and bunch-length monitor have been performed. For stable operation of the linac, many timing signals have to be monitored as well. To that end we have developed 32-bit multi-hit time-to-digital converters (TDCs) with 1-ns resolution. The first beam tests of those systems are reported in this paper.
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MOPD01	RHIC p-Carbon Polarimeter Target Lifetime Issue	polarization, proton, detector, simulation	124
	H. Huang, E.C. Aschenauer, G. Atoian, A. Bazilevsky, O. Eyser, A. Fernando, D.M. Gassner, D. Kalinkin, J. Kewisch, G.J. Mahler, Y. Makdisi, S. Nemesure, A. Poblaguev, W.B. Schmidke, D. Steski, T. Tsang, K. Yip, A. Zelenski BNL, Upton, Long Island, New York, USA I.G. Alekseev, D. Svirida ITEP, Moscow, Russia
	Funding: Work performed under contract No. DE-AC02-98CH1-886 with the auspices of the DOE of United States RHIC polarized proton operation requires fast and reliable proton polarimeter for polarization monitoring during stores. Polarimeters based on p-Carbon elastic scattering in the Coulomb Nuclear Interference(CNI) region has been used. Two polarimeters are installed in each of the two collider rings and they are capable to provide important polarization profile information. The polarimeter also provides valuable information for polarization loss on the energy ramp. As the intensity increases over years, the carbon target lifetime is getting shorter and target replacement during operation is necessary. Simulations and experiment tests have been done to address the target lifetime issue. This paper summarizes the recent operation and the target test results.
	Poster MOPD01 [10.776 MB]
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TUCYB1	Study of scintillation stability in KBr, YAG:Ce, CaF2:Eu and CsI:Tl Irradiated by Various-Energy Protons	ion, radiation, emittance, photon	250
	L.Y. Lin FRIB, East Lansing, Michigan, USA
	The luminescence of KBr, YAG:Ce, CaF2:Eu and CsI:Tl scintillators induced with H²⁺ ion beams in the energy range of 600-2150 keV/u has been systematically measured as a function of irradiation time. The measurements showed that the luminescence of CsI:Tl and YAG:Ce remained constant within the 1-hour continuous irradiation. An initial fast drop of the luminescence on CaF2:Eu was observed but the light output eventually approached a stable state under constant ion bombardment. We also observed that the light output of KBr initially increased and then degraded gradually with further irradiation. The CsI:Tl screen produced the highest scintillation yield and KBr the lowest.
	Slides TUCYB1 [2.078 MB]
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TUPF09	Calibration of OLYMPUS/DORIS Beam Position Monitors	electronics, experiment, positron, electron	324
	U. Schneekloth, N. Görrissen, G. Kube, J. Neugebauer, Ru. Neumann, F. Schmidt-Föhre DESY, Hamburg, Germany
	The goal of the OLYMPUS experiment is a precise measurement of the ratio of the positron-proton and electron-proton elastic scattering cross sections in order to quantify the effect of two-photon exchange. The experiment was performed using intense beams of electrons and positrons stored in the DORIS ring at Deutsches Elektronen Synchrotron in Hamburg, impinging on an un-polarized, internal, hydrogen gas target. An essential ingredient of the experiment is a precise determination of the luminosity, which requires a precise knowledge of the beam position of both beam species. During DORIS operation cylindrical button beam position monitors, read out by two independent electronics systems, were mounted up- and downstream of the target chamber. After the end of operation, the readout systems were cross-calibrated. The BPMs were then calibrated using a test-stand, consisting of a wire scanner assembly. The beam was simulated by applying an RF signal to the wire. This paper describes the calibration principles and test setup, together with the results compared to the expected BPM response.
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TUPF27	Optical System for ESS Target Protection	proton, FPGA, operation, radiation	389
	C.A. Thomas, M. Donna, T.J. Grandsaert, M. Göhran, R. Linander, T.J. Shea ESS, Lund, Sweden
	One specificity of the ESS accelerator and target is that a high power and ultra low emittance proton beam is sent straight onto a Tungsten target. The high power density proton beam from the ESS linac will damage any material it meets. Thus a strategy to protect the target and the target area has to be deployed: the proton beam on target will be defocused and swept, distributing homogeneously the power density on an area 10⁴ times larger than its non defocused area. On its way towards the target, the beam goes through two windows: the proton beam window (PBW) separating the high vacuum of the accelerator to the 1-bar He filled area of the target monolith; and the target window (TW) marking the entrance area of the target wheel. In this paper, we present the PBW imaging system, one of the proton beam diagnostics to be developed for imaging the proton beam current density deposited in the PBW. We will describe the expected performance of the imaging system in order to satisfy the PBW protection requirement. We will also describe the radiative processes which could be used as the source of the imaging system. Finally, we will describe the necessary condition and hardware for the implementation of a protection system for both the PBW and TW.
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TUPD09	Vacuum Improvement of Bunch Shape Monitor for J-PARC Linac	vacuum, high-voltage, electron, linac	430
	A. Miura, Y. Kawane, N. Ouchi JAEA/J-PARC, Tokai-mura, Japan T. Miyao KEK, Ibaraki, Japan
	During the shutdown in summer 2012, we installed three BSMs (Bunch Shape Monitors) at the upstream of the ACS (Annular Coupled Structure Linac) section in order to perform longitudinal matching. ACS cavities were installed in summer 2013 to upgrade the Linac energy from 181 MeV to 400 MeV. Prior to the ACS installation, BSMs were installed and the beam commissioning of the BSMs has been conducted after the summer shutdown in 2012. During the BSM measurements, a problem of the degradation in vacuum conditions was found. One reason for this problem is the dark current resulting in the desorption of absorbed gas molecules. And another reason is the outgas released from materials when the high voltage and RF power are supplied for the electro-static lens and RF deflector, respectively. In order to solve this problem, BSMs were dismounted from the beam line and the off-line baking operations with outgas analysis had been performed to avoid the degradation of the vacuum. As the result of the gas analysis, we found that the outgas contains some heavy hydrocarbons. After these heavy hydrocarbon gaseous were removed and the vacuum level improved for about one order, we completed off-line baking. We will install all three BSMs in at the upstream of the ACS again with the additional vacuum pumps. This paper describes the vacuum degradation of the BSMs, how to conduct the baking operation for BSMs and its results. The improved set-ups of the vacuum are also introduced.
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TUPD12	Development of Non-Invasive Electron Beam Position Monitor Based on Coherent Diffraction Radiation from a Slit	electron, radiation, detector, linac	442
	Y. Taira, R. Kuroda, M. Tanaka, H. Toyokawa AIST, Tsukuba, Ibaraki, Japan K. Sakaue Waseda University, Tokyo, Japan H. Tomizawa RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	Funding: This work was supported by Grants-in-Aid for Scientific Research (26246046). Diffraction radiation (DR), which is closely related to transition radiation, is emitted when an electron passes near an edge or interface between two media with different dielectric constants. Theoretical and experimental investigation of DR is widely performing for a non-intercepting electron beam diagnostic. We have developed an electron bunch length and a beam position monitor using a coherent diffraction radiation (CDR), which is in the range of sub-millimeter wavelength. The frequency spectrum of CDR depends on a form factor expressed as the Fourier transform of the longitudinal particle distribution. We have measured the spatial intensity distribution of CDR emitted from the metallic edge with a terahertz camera. Total intensity passing through band pass filters (BPFs) was decreased as the transmission frequency of BPFs is increased up to 6 THz. The result indicates that the bunch length is few hundreds of femtosecond. A detailed data analysis is now performing. On the other hand, we have measured the intensity distribution of CDR emitted from the metallic rectangular slit. Bow-tie intensity distribution, aligned along the perpendicular direction to the slit edge, was measured with the terahertz camera. Moreover, when the electron beam did not pass through the center of the slit, an asymmetrical intensity distribution appeared. This asymmetry is due to the pre-wave zone effect. In short, we can found the beam position to the slit by measuring the asymmetry. In this conference, we will present the experimental results.
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TUPD13	Experience with and Studies of the SNS Target Imaging System	neutron, simulation, proton, operation	447
	W. Blokland ORNL, Oak Ridge, Tennessee, USA
	Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725 The Target Imaging System (TIS) shows the size and position of the proton beam by using a luminescent Cr:Al2O3 coating on the SNS target. The proton beam hitting the coating creates light which is transferred through mirrors and optical fibers to a digital camera outside the high radiation area. The TIS is used during operations to verify that the beam is in the right location and does not exceed the maximum proton beam peak density. This paper describes our operational experience with the TIS and the results of studies on the linearity, uniformity, and luminescence decay of the coating. In the future, tubes with material samples might be placed in front of the target for irradiation studies. The simulations of placing tubes in the front of target coating and its effect on the beam width and position measurements are also discussed.
	Poster TUPD13 [3.216 MB]
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TUPD16	Development of the Transverse Beam Profile Monitors for the PAL-XFEL	electron, diagnostics, radiation, vacuum	452
	I.Y. Kim, J.Y. Choi, H. Heo, H.-S. Kang, C. Kim, G. Mun, B.G. Oh, S.J. Park PAL, Pohang, Kyungbuk, Republic of Korea
	The PAL-XFEL is an X-ray free electron laser under construnction at the Pohang Accelerator Laboratory (PAL), Korea. In the PAL-XFEL, the electron beam can make coherent optical transition radiation (COTR) due to the microbunching instability in the compressed electron beam. In order to obtain transverse beam profiles without the COTR problem, we are developing scintillating screen monitors (with the geometric suppress method) and wire scanners. In this paper, we report test results at the test facility and progress in the development of the screen monitor and the wire scanner for the PAL-XFEL.
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WEPF17	Error Analysis for Pepperpot Emittance Measurements Redux: Correlated Phase Spaces	emittance, background, diagnostics, ion	579
	S.M. Lidia FRIB, East Lansing, Michigan, USA K. Murphy LBNL, Berkeley, California, USA
	Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Recently, Jolly et al. presented an analysis of the rms emittance measurement errors from a first principles approach [1]. Their approach demonstrated the propagation of errors in the single-plane rms emittance determination from several instrument and beam related sources. We have extended the analysis of error propagation and estimation to the fully correlated 4-D phase space emittances obtained from pepperpot measurements. We present the calculation of the variances using a Cholesky decomposition approach. Pepperpot data from recent experiments on the NDCX-II beamline are described, and estimates of the emittances and measurement errors for the 4-D as well as the projected rms emittances in this coupled system are presented. [1] S. Jolly, et al., “Data Acquisition and Error Analysis for Pepperpot Emittance Measurements”, Proceedings of DIPAC ’09, WEOA03.
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WEPF23	Dosimetric Verification of Lateral Profile with a Unique Ionization Chamber in Therapeutic Ion Beams	ion, factory, proton, scattering	597
	Y. Hara, T. Furukawa, K. Mizushima, K. Noda, N. S. Saotome, T. Shirai, R. Tansho NIRS, Chiba-shi, Japan Y. Saraya National Institute of Radiological Sciences, Chiba, Japan
	It is essential to consider large-angle scattered particles in dose calculation models for therapeutic ion beams. However, it is difﬁcult to measure the small dose contribution from large-angle scattered particles. Therefore, we developed a parallel-plate ionization chamber consisting of concentric electrodes (ICCE) to efﬁciently and easily detect small contributions. The ICCE consists of two successive ICs with a common HV plate. The former is a large plane-parallel IC to measure dose distribution integrated over the whole plane, the latter is a 24-channel parallel-plate IC with concentric electrodes to derive the characteristic parameters describing the lateral beam spread. The aim of this study is to evaluate the performance of the ICCE. By taking advantage of the characteristic of ICCE, we studied the recombination associated with lateral beam profile. Also, we measured carbon pencil beam in several different media by using ICCE. As a result, we confirmed the ICCE could be used as a useful tool to determine the characterization of the therapeutic ion beams.
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WEPF26	The Brookhaven LINAC Isotope Production Facility (BLIP) Raster Scanning Upgrade	controls, laser, power-supply, radiation	608
	R.J. Michnoff, Z. Altinbas, P. Cerniglia, R. Connolly, C. Cullen, C. Degen, D.M. Gassner, R.L. Hulsart, R.F. Lambiase, L.F. Mausner, D. Raparia, P. Thieberger, M. Wilinski BNL, Upton, Long Island, New York, USA
	Brookhaven National Laboratory’s BLIP facility produces radioisotopes for the nuclear medicine community and industry, and performs research to develop new radioisotopes desired by nuclear medicine investigators. A raster scanning system is being installed to provide a better distribution of the H⁻ beam on the targets, allow higher beam intensities to be used, and ultimately increase production yield of the isotopes. The upgrade consists of horizontal and vertical dipole magnets sinusoidally driven at 5 kHz with 90 deg phase separation to produce a circular raster pattern, and a suite of new instrumentation devices to measure beam characteristics and allow adequate machine protection. The instrumentation systems include multi-wire profile monitors, a laser profile monitor, beam current transformers, and a beam position monitor. An overview of the upgrade and project status will be presented. Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
	Poster WEPF26 [2.002 MB]
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Paper

Title

Other Keywords

Page

MOPF14

Vertical Beam Size Measurement at CesrTA Using Diffraction Radiation

radiation, electron, background, polarization

77

L.M. Bobb, T. Aumeyr, P. Karataev
JAI, Egham, Surrey, United Kingdom
T. Aumeyr, P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom
M.G. Billing, J.V. Conway
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
L.M. Bobb
DLS, Oxfordshire, United Kingdom
E. Bravin, T. Lefèvre, S. Mazzoni, H. Schmickler
CERN, Geneva, Switzerland

Over recent years the first Diffraction Radiation (DR) beam size monitor has been tested on a circular machine. At CesrTA, Cornell University, USA, the sensitivity and limitations of the DR monitor for vertical beam size measurement has been investigated. DR emitted from 1 and 0.5 mm target apertures was observed at 400 and 600 nm wavelengths. In addition, interference between the DR signals emitted by the target and mask has been observed. In this report, we present the recent observations and discuss areas for improvement.

Poster MOPF14 [3.379 MB]

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MOPF28

Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac

linac, timing, electron, positron

110

F. Miyahara, K. Furukawa, R. Ichimiya, N. Iida, M. Ikeno, H. Kaji, M. Satoh, M. Shoji, T. Suwada, M. Tanaka, Y. Yano
KEK, Ibaraki, Japan
T. Okazaki
EJIT, Hitachi, Ibaraki, Japan

The SuperKEKB injector linac has multiple operation modes for the electron beam injection into 3 separate rings, SuperKEKB HER, PF (Photon Factory) Ring and PF-AR, and the positron beam injection into the damping ring and the SuperKEKB LER. The operation modes can be switched every 20 milli-second with arbitrary order. The beam parameters such as charge, energy and emittance are different for each of the rings. Moreover, the bunch charge of the electron beam, 5nC, is 5 times higher and the emittance of ~10 mm•mrad is 30 times lower than those of the KEKB injector. Thus, development of BPM readout system with a wide dynamic range and installation of optical fiber detector with a good S/N ratio for the wire scanners and bunch-length monitor have been performed. For stable operation of the linac, many timing signals have to be monitored as well. To that end we have developed 32-bit multi-hit time-to-digital converters (TDCs) with 1-ns resolution. The first beam tests of those systems are reported in this paper.

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MOPD01

RHIC p-Carbon Polarimeter Target Lifetime Issue

polarization, proton, detector, simulation

124

H. Huang, E.C. Aschenauer, G. Atoian, A. Bazilevsky, O. Eyser, A. Fernando, D.M. Gassner, D. Kalinkin, J. Kewisch, G.J. Mahler, Y. Makdisi, S. Nemesure, A. Poblaguev, W.B. Schmidke, D. Steski, T. Tsang, K. Yip, A. Zelenski
BNL, Upton, Long Island, New York, USA
I.G. Alekseev, D. Svirida
ITEP, Moscow, Russia

Funding: Work performed under contract No. DE-AC02-98CH1-886 with the auspices of the DOE of United States
RHIC polarized proton operation requires fast and reliable proton polarimeter for polarization monitoring during stores. Polarimeters based on p-Carbon elastic scattering in the Coulomb Nuclear Interference(CNI) region has been used. Two polarimeters are installed in each of the two collider rings and they are capable to provide important polarization profile information. The polarimeter also provides valuable information for polarization loss on the energy ramp. As the intensity increases over years, the carbon target lifetime is getting shorter and target replacement during operation is necessary. Simulations and experiment tests have been done to address the target lifetime issue. This paper summarizes the recent operation and the target test results.

Poster MOPD01 [10.776 MB]

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TUCYB1

Study of scintillation stability in KBr, YAG:Ce, CaF2:Eu and CsI:Tl Irradiated by Various-Energy Protons

ion, radiation, emittance, photon

250

L.Y. Lin
FRIB, East Lansing, Michigan, USA

The luminescence of KBr, YAG:Ce, CaF2:Eu and CsI:Tl scintillators induced with H²⁺ ion beams in the energy range of 600-2150 keV/u has been systematically measured as a function of irradiation time. The measurements showed that the luminescence of CsI:Tl and YAG:Ce remained constant within the 1-hour continuous irradiation. An initial fast drop of the luminescence on CaF2:Eu was observed but the light output eventually approached a stable state under constant ion bombardment. We also observed that the light output of KBr initially increased and then degraded gradually with further irradiation. The CsI:Tl screen produced the highest scintillation yield and KBr the lowest.

Slides TUCYB1 [2.078 MB]

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TUPF09

Calibration of OLYMPUS/DORIS Beam Position Monitors

electronics, experiment, positron, electron

324

U. Schneekloth, N. Görrissen, G. Kube, J. Neugebauer, Ru. Neumann, F. Schmidt-Föhre
DESY, Hamburg, Germany

The goal of the OLYMPUS experiment is a precise measurement of the ratio of the positron-proton and electron-proton elastic scattering cross sections in order to quantify the effect of two-photon exchange. The experiment was performed using intense beams of electrons and positrons stored in the DORIS ring at Deutsches Elektronen Synchrotron in Hamburg, impinging on an un-polarized, internal, hydrogen gas target. An essential ingredient of the experiment is a precise determination of the luminosity, which requires a precise knowledge of the beam position of both beam species. During DORIS operation cylindrical button beam position monitors, read out by two independent electronics systems, were mounted up- and downstream of the target chamber. After the end of operation, the readout systems were cross-calibrated. The BPMs were then calibrated using a test-stand, consisting of a wire scanner assembly. The beam was simulated by applying an RF signal to the wire. This paper describes the calibration principles and test setup, together with the results compared to the expected BPM response.

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TUPF27

Optical System for ESS Target Protection

proton, FPGA, operation, radiation

389

C.A. Thomas, M. Donna, T.J. Grandsaert, M. Göhran, R. Linander, T.J. Shea
ESS, Lund, Sweden

One specificity of the ESS accelerator and target is that a high power and ultra low emittance proton beam is sent straight onto a Tungsten target. The high power density proton beam from the ESS linac will damage any material it meets. Thus a strategy to protect the target and the target area has to be deployed: the proton beam on target will be defocused and swept, distributing homogeneously the power density on an area 10⁴ times larger than its non defocused area. On its way towards the target, the beam goes through two windows: the proton beam window (PBW) separating the high vacuum of the accelerator to the 1-bar He filled area of the target monolith; and the target window (TW) marking the entrance area of the target wheel. In this paper, we present the PBW imaging system, one of the proton beam diagnostics to be developed for imaging the proton beam current density deposited in the PBW. We will describe the expected performance of the imaging system in order to satisfy the PBW protection requirement. We will also describe the radiative processes which could be used as the source of the imaging system. Finally, we will describe the necessary condition and hardware for the implementation of a protection system for both the PBW and TW.

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TUPD09

Vacuum Improvement of Bunch Shape Monitor for J-PARC Linac

vacuum, high-voltage, electron, linac

430

A. Miura, Y. Kawane, N. Ouchi
JAEA/J-PARC, Tokai-mura, Japan
T. Miyao
KEK, Ibaraki, Japan

During the shutdown in summer 2012, we installed three BSMs (Bunch Shape Monitors) at the upstream of the ACS (Annular Coupled Structure Linac) section in order to perform longitudinal matching. ACS cavities were installed in summer 2013 to upgrade the Linac energy from 181 MeV to 400 MeV. Prior to the ACS installation, BSMs were installed and the beam commissioning of the BSMs has been conducted after the summer shutdown in 2012. During the BSM measurements, a problem of the degradation in vacuum conditions was found. One reason for this problem is the dark current resulting in the desorption of absorbed gas molecules. And another reason is the outgas released from materials when the high voltage and RF power are supplied for the electro-static lens and RF deflector, respectively. In order to solve this problem, BSMs were dismounted from the beam line and the off-line baking operations with outgas analysis had been performed to avoid the degradation of the vacuum. As the result of the gas analysis, we found that the outgas contains some heavy hydrocarbons. After these heavy hydrocarbon gaseous were removed and the vacuum level improved for about one order, we completed off-line baking. We will install all three BSMs in at the upstream of the ACS again with the additional vacuum pumps. This paper describes the vacuum degradation of the BSMs, how to conduct the baking operation for BSMs and its results. The improved set-ups of the vacuum are also introduced.

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TUPD12

Development of Non-Invasive Electron Beam Position Monitor Based on Coherent Diffraction Radiation from a Slit

electron, radiation, detector, linac

442

Y. Taira, R. Kuroda, M. Tanaka, H. Toyokawa
AIST, Tsukuba, Ibaraki, Japan
K. Sakaue
Waseda University, Tokyo, Japan
H. Tomizawa
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan

Funding: This work was supported by Grants-in-Aid for Scientific Research (26246046).
Diffraction radiation (DR), which is closely related to transition radiation, is emitted when an electron passes near an edge or interface between two media with different dielectric constants. Theoretical and experimental investigation of DR is widely performing for a non-intercepting electron beam diagnostic. We have developed an electron bunch length and a beam position monitor using a coherent diffraction radiation (CDR), which is in the range of sub-millimeter wavelength. The frequency spectrum of CDR depends on a form factor expressed as the Fourier transform of the longitudinal particle distribution. We have measured the spatial intensity distribution of CDR emitted from the metallic edge with a terahertz camera. Total intensity passing through band pass filters (BPFs) was decreased as the transmission frequency of BPFs is increased up to 6 THz. The result indicates that the bunch length is few hundreds of femtosecond. A detailed data analysis is now performing. On the other hand, we have measured the intensity distribution of CDR emitted from the metallic rectangular slit. Bow-tie intensity distribution, aligned along the perpendicular direction to the slit edge, was measured with the terahertz camera. Moreover, when the electron beam did not pass through the center of the slit, an asymmetrical intensity distribution appeared. This asymmetry is due to the pre-wave zone effect. In short, we can found the beam position to the slit by measuring the asymmetry. In this conference, we will present the experimental results.

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TUPD13

Experience with and Studies of the SNS Target Imaging System

neutron, simulation, proton, operation

447

W. Blokland
ORNL, Oak Ridge, Tennessee, USA

Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725
The Target Imaging System (TIS) shows the size and position of the proton beam by using a luminescent Cr:Al2O3 coating on the SNS target. The proton beam hitting the coating creates light which is transferred through mirrors and optical fibers to a digital camera outside the high radiation area. The TIS is used during operations to verify that the beam is in the right location and does not exceed the maximum proton beam peak density. This paper describes our operational experience with the TIS and the results of studies on the linearity, uniformity, and luminescence decay of the coating. In the future, tubes with material samples might be placed in front of the target for irradiation studies. The simulations of placing tubes in the front of target coating and its effect on the beam width and position measurements are also discussed.

Poster TUPD13 [3.216 MB]

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TUPD16

Development of the Transverse Beam Profile Monitors for the PAL-XFEL

electron, diagnostics, radiation, vacuum

452

I.Y. Kim, J.Y. Choi, H. Heo, H.-S. Kang, C. Kim, G. Mun, B.G. Oh, S.J. Park
PAL, Pohang, Kyungbuk, Republic of Korea

The PAL-XFEL is an X-ray free electron laser under construnction at the Pohang Accelerator Laboratory (PAL), Korea. In the PAL-XFEL, the electron beam can make coherent optical transition radiation (COTR) due to the microbunching instability in the compressed electron beam. In order to obtain transverse beam profiles without the COTR problem, we are developing scintillating screen monitors (with the geometric suppress method) and wire scanners. In this paper, we report test results at the test facility and progress in the development of the screen monitor and the wire scanner for the PAL-XFEL.

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WEPF17

Error Analysis for Pepperpot Emittance Measurements Redux: Correlated Phase Spaces

emittance, background, diagnostics, ion

579

S.M. Lidia
FRIB, East Lansing, Michigan, USA
K. Murphy
LBNL, Berkeley, California, USA

Funding: This work was supported by the Director, Office of Science, Office of Fusion Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
Recently, Jolly et al. presented an analysis of the rms emittance measurement errors from a first principles approach [1]. Their approach demonstrated the propagation of errors in the single-plane rms emittance determination from several instrument and beam related sources. We have extended the analysis of error propagation and estimation to the fully correlated 4-D phase space emittances obtained from pepperpot measurements. We present the calculation of the variances using a Cholesky decomposition approach. Pepperpot data from recent experiments on the NDCX-II beamline are described, and estimates of the emittances and measurement errors for the 4-D as well as the projected rms emittances in this coupled system are presented.
[1] S. Jolly, et al., “Data Acquisition and Error Analysis for Pepperpot Emittance Measurements”, Proceedings of DIPAC ’09, WEOA03.

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WEPF23

Dosimetric Verification of Lateral Profile with a Unique Ionization Chamber in Therapeutic Ion Beams

ion, factory, proton, scattering

597

Y. Hara, T. Furukawa, K. Mizushima, K. Noda, N. S. Saotome, T. Shirai, R. Tansho
NIRS, Chiba-shi, Japan
Y. Saraya
National Institute of Radiological Sciences, Chiba, Japan

It is essential to consider large-angle scattered particles in dose calculation models for therapeutic ion beams. However, it is difﬁcult to measure the small dose contribution from large-angle scattered particles. Therefore, we developed a parallel-plate ionization chamber consisting of concentric electrodes (ICCE) to efﬁciently and easily detect small contributions. The ICCE consists of two successive ICs with a common HV plate. The former is a large plane-parallel IC to measure dose distribution integrated over the whole plane, the latter is a 24-channel parallel-plate IC with concentric electrodes to derive the characteristic parameters describing the lateral beam spread. The aim of this study is to evaluate the performance of the ICCE. By taking advantage of the characteristic of ICCE, we studied the recombination associated with lateral beam profile. Also, we measured carbon pencil beam in several different media by using ICCE. As a result, we confirmed the ICCE could be used as a useful tool to determine the characterization of the therapeutic ion beams.

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WEPF26

The Brookhaven LINAC Isotope Production Facility (BLIP) Raster Scanning Upgrade

controls, laser, power-supply, radiation

608

R.J. Michnoff, Z. Altinbas, P. Cerniglia, R. Connolly, C. Cullen, C. Degen, D.M. Gassner, R.L. Hulsart, R.F. Lambiase, L.F. Mausner, D. Raparia, P. Thieberger, M. Wilinski
BNL, Upton, Long Island, New York, USA

Brookhaven National Laboratory’s BLIP facility produces radioisotopes for the nuclear medicine community and industry, and performs research to develop new radioisotopes desired by nuclear medicine investigators. A raster scanning system is being installed to provide a better distribution of the H⁻ beam on the targets, allow higher beam intensities to be used, and ultimately increase production yield of the isotopes. The upgrade consists of horizontal and vertical dipole magnets sinusoidally driven at 5 kHz with 90 deg phase separation to produce a circular raster pattern, and a suite of new instrumentation devices to measure beam characteristics and allow adequate machine protection. The instrumentation systems include multi-wire profile monitors, a laser profile monitor, beam current transformers, and a beam position monitor. An overview of the upgrade and project status will be presented.
Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy

Poster WEPF26 [2.002 MB]

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