IBIC2012 - List of Keywords (cathode)

Paper	Title	Other Keywords	Page
MOPA48	Measurement of Temporal Resolution and Detection Efficiency of X-ray Streak Camera by Single Photon Images	photon, timing, experiment, electron	171
	A. Mochihashi, M. Masaki, H. Ohkuma, S. Takano, K. Tamura JASRI/SPring-8, Hyogo-ken, Japan
	Funding: This work was partly supported by MEXT Grant-in-Aid for Young Scientists (B) Grant number 21740215. In the third generation and the next generation synchrotron radiation light sources, the electron beam bunch length of ps ~ sub-ps is expected to be achieved. An X-ray streak camera (X-SC) can directly measure the temporal width of X-ray synchrotron radiation pulse. The temporal resolution of X-SC depends on the initial velocity distribution of the photoelectrons from a photocathode which converts the X-ray photons to the photoelectrons. To measure the temporal resolution of the X-SC, we have observed 'single photon' streak camera images and measured the temporal spread of the images. By this 'single photon' experiment, we have evaluated the dependence of the temporal resolution and the detection efficiency on the photon energy. We have also tried to evaluate the dependence of the temporal resolution and the detection efficiency on the thickness of the photocathode. For this purpose, we have developed a multi-array type CsI photocathode with 3 different thickness of the photocathode. The experimental setups, and the results of the measurements of the temporal spread and the detection efficiency of the single photon events will be presented.

MOPB51	Beam Monitors of NIRS Fast Scanning System for Particle Therapy	ion, controls, monitoring, vacuum	182
	T. Furukawa, Y. Hara, T. Inaniwa, K. Katagiri, K. Mizushima, K. Noda, S. Sato, T. Shirai, E. Takeshita NIRS, Chiba-shi, Japan
	At National Institute of Radiological Sciences, more than 6500 patients have been successfully treated by carbon beams since 1994. The successful results of treatments have led us to construct a new treatment facility equipped with three-dimensional pencil beam scanning irradiation system. The commissioning of NIRS fast scanning system installed into the new facility was started in September 2010, and the treatment with scanned ion beam was started in May 2011. In the scanning delivery system, beam monitors are some of the most important components. In order to measure and control the dose of each spot, the main and the sub ionization chambers are placed separately as flux monitors. For monitoring of the scanned beam position, a beam position monitor, which is multi-wire proportional chamber, is installed just downstream from the flux monitors. This monitor can output not only the beam position but also the 2D fluence distribution using dynamic fast convolution algorithm. In this paper, the design and the commissioning of these monitors are described.

MOPB73	Beam Size and Intensity Diagnostics for a SRF Photoelectron Injector	electron, gun, solenoid, scattering	241
	R. Barday, A. Jankowiak, T. Kamps, A.N. Matveenko, M. Schenk, J. Völker HZB, Berlin, Germany F. Siewert BESSY GmbH, Berlin, Germany J. Teichert HZDR, Dresden, Germany
	Funding: Work supported by Bundesministerium für Bildung und Forschung and Land Berlin A high brightness photoelectron injector must be developed as a part of the BERLinPro program. The injector is designed to produce an electron beam with 100 mA average current and a normalized emittance of 1 mm*mrad. The project will be realized in two stages. First with a Pb cathode in a SRF gun, work ongoing, followed by a normal conducting CsK2Sb cathode capable of generating high current beams. In the first stage we have measured the fundamental beam parameters bunch charge, beam energy and energy spread with a special focus on the measurement of the transverse beam profiles. We also discuss our plans for the beam characterization at high currents.

TUPB51	Gatling Gun Test Stand Instrumentation	electron, gun, diagnostics, emittance	474
	D.M. Gassner, I. Ben-Zvi, J.C. Brutus, C. Liu, M.G. Minty, A.I. Pikin, O.H. Rahman, E.J. Riehn, J. Skaritka, E. Wang BNL, Upton, Long Island, New York, USA
	In order to reach the design eRHIC luminosity 50mA of polarized electron current is needed. This is far beyond what the present state-of-the-art polarized electron cathode can deliver. A high average polarized current injector based on the Gatling Gun principle is being designed. This technique will employ multiple cathodes and combine their multiple bunched beams along the same axis. A proof-of-principle test bench will be constructed that includes a 220 keV Gatling Gun, beam combiner, diagnostics station, and collector. The challenges for the instrumentation systems and the beam diagnostics that will measure current, profile, position, and halo will be described.

TUPB69	Numerical Analysis on the Gain-reduction Characteristics of Multi-wire Proportional Chambers	ion, simulation, electron, space-charge	502
	K. Katagiri, T. Furukawa, K. Noda NIRS, Chiba-shi, Japan
	Several MWPC (Multi-Wire Proportional Chamber) monitors are installed to diagnosis the beam profiles in the high-energy beam transport at HIMAC (Heavy Ion Medical Accelerator in Chiba) synchrotrons. When the intensity of the incident beams are much high, the gain reduction of the output signal from the MWPC monitor occurs due to the space charge effect of positive ions around the anode wires. The gain reduction is expected to be improved by changing geometric parameters, such as anode radius and distance between electrodes. In order to investigate the gain-reduction characteristics for different geometric parameters, we performed numerical simulation using a numerical code. The numerical code was developed using a two-dimensional drift-diffusion model to evaluate the gas gain including the reduction effect caused by the space charge effect of the moving positive ions. We investigate the gain-reduction rate for several parameters of the anode distance when changing the beam intensity. From these results, we discuss desirable distances between the anode wires to improve the gain reduction.

THCB01	Electron-Lens Test Stand Instrumentation Progress	gun, electron, laser, instrumentation	602
	T.A. Miller, J.N. Aronson, D.M. Gassner, X. Gu, A.I. Pikin, P. Thieberger BNL, Upton, Long Island, New York, USA
	Funding: Work supported by B.S.A, LLC under contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. In preparation for installation of Electron Lenses into RHIC, planned for late 2012, a working test stand is in use testing the performance of the gun, collector, modulator, instrumentation and controls. While testing & operating the instrumentation, both progress and pitfalls were encountered. Results are presented from issues including ground loop signals generated by the DCCTs, static magnetic field interference, competing YAG screen illumination techniques, YAG crystal damage during beam operation, performance of the four quadrant beam scraper electrodes, and challenges in measuring beam current in conductors. Working knowledge and insight into each of these systems has been gained through difficulties leading to success. These insights are presented with supporting data and images.
	Slides THCB01 [32.453 MB]

Paper

Title

Other Keywords

Page

MOPA48

Measurement of Temporal Resolution and Detection Efficiency of X-ray Streak Camera by Single Photon Images

photon, timing, experiment, electron

171

A. Mochihashi, M. Masaki, H. Ohkuma, S. Takano, K. Tamura
JASRI/SPring-8, Hyogo-ken, Japan

Funding: This work was partly supported by MEXT Grant-in-Aid for Young Scientists (B) Grant number 21740215.
In the third generation and the next generation synchrotron radiation light sources, the electron beam bunch length of ps ~ sub-ps is expected to be achieved. An X-ray streak camera (X-SC) can directly measure the temporal width of X-ray synchrotron radiation pulse. The temporal resolution of X-SC depends on the initial velocity distribution of the photoelectrons from a photocathode which converts the X-ray photons to the photoelectrons. To measure the temporal resolution of the X-SC, we have observed 'single photon' streak camera images and measured the temporal spread of the images. By this 'single photon' experiment, we have evaluated the dependence of the temporal resolution and the detection efficiency on the photon energy. We have also tried to evaluate the dependence of the temporal resolution and the detection efficiency on the thickness of the photocathode. For this purpose, we have developed a multi-array type CsI photocathode with 3 different thickness of the photocathode. The experimental setups, and the results of the measurements of the temporal spread and the detection efficiency of the single photon events will be presented.

MOPB51

Beam Monitors of NIRS Fast Scanning System for Particle Therapy

ion, controls, monitoring, vacuum

182

T. Furukawa, Y. Hara, T. Inaniwa, K. Katagiri, K. Mizushima, K. Noda, S. Sato, T. Shirai, E. Takeshita
NIRS, Chiba-shi, Japan

At National Institute of Radiological Sciences, more than 6500 patients have been successfully treated by carbon beams since 1994. The successful results of treatments have led us to construct a new treatment facility equipped with three-dimensional pencil beam scanning irradiation system. The commissioning of NIRS fast scanning system installed into the new facility was started in September 2010, and the treatment with scanned ion beam was started in May 2011. In the scanning delivery system, beam monitors are some of the most important components. In order to measure and control the dose of each spot, the main and the sub ionization chambers are placed separately as flux monitors. For monitoring of the scanned beam position, a beam position monitor, which is multi-wire proportional chamber, is installed just downstream from the flux monitors. This monitor can output not only the beam position but also the 2D fluence distribution using dynamic fast convolution algorithm. In this paper, the design and the commissioning of these monitors are described.

MOPB73

Beam Size and Intensity Diagnostics for a SRF Photoelectron Injector

electron, gun, solenoid, scattering

241

R. Barday, A. Jankowiak, T. Kamps, A.N. Matveenko, M. Schenk, J. Völker
HZB, Berlin, Germany
F. Siewert
BESSY GmbH, Berlin, Germany
J. Teichert
HZDR, Dresden, Germany

Funding: Work supported by Bundesministerium für Bildung und Forschung and Land Berlin
A high brightness photoelectron injector must be developed as a part of the BERLinPro program. The injector is designed to produce an electron beam with 100 mA average current and a normalized emittance of 1 mm*mrad. The project will be realized in two stages. First with a Pb cathode in a SRF gun, work ongoing, followed by a normal conducting CsK2Sb cathode capable of generating high current beams. In the first stage we have measured the fundamental beam parameters bunch charge, beam energy and energy spread with a special focus on the measurement of the transverse beam profiles. We also discuss our plans for the beam characterization at high currents.

TUPB51

Gatling Gun Test Stand Instrumentation

electron, gun, diagnostics, emittance

474

D.M. Gassner, I. Ben-Zvi, J.C. Brutus, C. Liu, M.G. Minty, A.I. Pikin, O.H. Rahman, E.J. Riehn, J. Skaritka, E. Wang
BNL, Upton, Long Island, New York, USA

In order to reach the design eRHIC luminosity 50mA of polarized electron current is needed. This is far beyond what the present state-of-the-art polarized electron cathode can deliver. A high average polarized current injector based on the Gatling Gun principle is being designed. This technique will employ multiple cathodes and combine their multiple bunched beams along the same axis. A proof-of-principle test bench will be constructed that includes a 220 keV Gatling Gun, beam combiner, diagnostics station, and collector. The challenges for the instrumentation systems and the beam diagnostics that will measure current, profile, position, and halo will be described.

TUPB69

Numerical Analysis on the Gain-reduction Characteristics of Multi-wire Proportional Chambers

ion, simulation, electron, space-charge

502

K. Katagiri, T. Furukawa, K. Noda
NIRS, Chiba-shi, Japan

Several MWPC (Multi-Wire Proportional Chamber) monitors are installed to diagnosis the beam profiles in the high-energy beam transport at HIMAC (Heavy Ion Medical Accelerator in Chiba) synchrotrons. When the intensity of the incident beams are much high, the gain reduction of the output signal from the MWPC monitor occurs due to the space charge effect of positive ions around the anode wires. The gain reduction is expected to be improved by changing geometric parameters, such as anode radius and distance between electrodes. In order to investigate the gain-reduction characteristics for different geometric parameters, we performed numerical simulation using a numerical code. The numerical code was developed using a two-dimensional drift-diffusion model to evaluate the gas gain including the reduction effect caused by the space charge effect of the moving positive ions. We investigate the gain-reduction rate for several parameters of the anode distance when changing the beam intensity. From these results, we discuss desirable distances between the anode wires to improve the gain reduction.

THCB01

Electron-Lens Test Stand Instrumentation Progress

gun, electron, laser, instrumentation

602

T.A. Miller, J.N. Aronson, D.M. Gassner, X. Gu, A.I. Pikin, P. Thieberger
BNL, Upton, Long Island, New York, USA

Funding: Work supported by B.S.A, LLC under contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
In preparation for installation of Electron Lenses into RHIC, planned for late 2012, a working test stand is in use testing the performance of the gun, collector, modulator, instrumentation and controls. While testing & operating the instrumentation, both progress and pitfalls were encountered. Results are presented from issues including ground loop signals generated by the DCCTs, static magnetic field interference, competing YAG screen illumination techniques, YAG crystal damage during beam operation, performance of the four quadrant beam scraper electrodes, and challenges in measuring beam current in conductors. Working knowledge and insight into each of these systems has been gained through difficulties leading to success. These insights are presented with supporting data and images.

Slides THCB01 [32.453 MB]