IBIC2014 - List of Keywords (positron)

Paper	Title	Other Keywords	Page
MOPF28	Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac	linac, timing, electron, target	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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TUPF09	Calibration of OLYMPUS/DORIS Beam Position Monitors	electronics, experiment, target, 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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TUPD22	Beam Loss Monitor at SuperKEKB	ion, electronics, injection, hardware	459
	H. Ikeda, M. Arinaga, J.W. Flanagan, H. Fukuma, M. Tobiyama KEK, Ibaraki, Japan
	We will use beam loss monitors for protection of the hardware of SuperKEKB against the unexpected sudden beam loss. The sensors are ion chambers and PIN photo-diodes. The loss monitor system gives an important trigger for the beam abort system. We can optimize the threshold of the abort trigger by checking the beam information at each abort moment. This paper explains the overall system of the SuperKEKB beam loss monitors including the damping ring.
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WEPF21	Electron Cloud Density Measurements Using Resonant Microwaves at CesrTA	resonance, electron, storage-ring, photon	592
	J.P. Sikora Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA S. De Santis LBNL, Berkeley, California, USA
	Funding: This work is supported by the US National Science Foundation PHY-0734867, PHY-1002467, and the US Department of Energy DE-FC02-08ER41538, DE-SC0006505. Hardware has recently been installed in the Cornell Electron Storage Ring (CESR) to extend the capability of resonant microwave measurement of electron cloud density. Two new detector locations include aluminum beam-pipe in a dipole magnet and copper beam-pipe in a field free region. Measurements with both positron and electron beams are presented with both beams showing saturation of the electron cloud density in the aluminum chamber. These measurements were made at CESR which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.
	Poster WEPF21 [1.988 MB]
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WEPD04	High Position Resolution and High Dynamic Range Stripline Beam Position Monitor (BPM) Readout System for the KEKB Injector Linac Towards the SuperKEKB	linac, alignment, electron, rf-amplifier	637
	R. Ichimiya, K. Furukawa, F. Miyahara, M. Satoh, T. Suwada KEK, Ibaraki, Japan
	The SuperKEKB accelerator is now being upgraded to bring the world highest luminosity (L=8x10³⁵/cm²/s). Hence, the KEKB injector linac has to produce low emittance and high charge electron (20 mm mrad, 7 GeV/c², 5 nC) and positron (20 mm mrad, 4 GeV/c², 4 nC) beam, respectively. In order to achieve these criteria, the accelerator structure has to be aligned within 0.1 mm position error. Since BPMs are essential instruments for beam based alignment (BBA), it is required to have one magnitude better position resolution to get enough alignment results. We have begun to develop high position resolution BPM readout system with narrow bandpass filters (fc = 180 MHz) and 250 MSa/s 16-bit ADCs. It handles two bunches with 96 ns interval separately and has a dynamic range from 0.1 nC to 10 nC. To compensate circuit drift, two calibration (x-direction and y-direction) pulses are output to the BPM electrodes between beam cycles (20 ms). Since it needs to achieve not only high position resolution but also good position accuracy, overall non-linearity within ±0.02 dB is required and the system has to have more than ±5 mm accurate position range. We confirmed the system performance with a 3-BPM resolution tests at KEK Injector Linac and it turned out that the system has 3 μm position resolution. We plan to install this system during 2015 summer shutdown.
	Poster WEPD04 [0.828 MB]
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Paper

Title

Other Keywords

Page

MOPF28

Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac

linac, timing, electron, target

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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TUPF09

Calibration of OLYMPUS/DORIS Beam Position Monitors

electronics, experiment, target, 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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TUPD22

Beam Loss Monitor at SuperKEKB

ion, electronics, injection, hardware

459

H. Ikeda, M. Arinaga, J.W. Flanagan, H. Fukuma, M. Tobiyama
KEK, Ibaraki, Japan

We will use beam loss monitors for protection of the hardware of SuperKEKB against the unexpected sudden beam loss. The sensors are ion chambers and PIN photo-diodes. The loss monitor system gives an important trigger for the beam abort system. We can optimize the threshold of the abort trigger by checking the beam information at each abort moment. This paper explains the overall system of the SuperKEKB beam loss monitors including the damping ring.

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WEPF21

Electron Cloud Density Measurements Using Resonant Microwaves at CesrTA

resonance, electron, storage-ring, photon

592

J.P. Sikora
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
S. De Santis
LBNL, Berkeley, California, USA

Funding: This work is supported by the US National Science Foundation PHY-0734867, PHY-1002467, and the US Department of Energy DE-FC02-08ER41538, DE-SC0006505.
Hardware has recently been installed in the Cornell Electron Storage Ring (CESR) to extend the capability of resonant microwave measurement of electron cloud density. Two new detector locations include aluminum beam-pipe in a dipole magnet and copper beam-pipe in a field free region. Measurements with both positron and electron beams are presented with both beams showing saturation of the electron cloud density in the aluminum chamber. These measurements were made at CESR which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.

Poster WEPF21 [1.988 MB]

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WEPD04

High Position Resolution and High Dynamic Range Stripline Beam Position Monitor (BPM) Readout System for the KEKB Injector Linac Towards the SuperKEKB

linac, alignment, electron, rf-amplifier

637

R. Ichimiya, K. Furukawa, F. Miyahara, M. Satoh, T. Suwada
KEK, Ibaraki, Japan

The SuperKEKB accelerator is now being upgraded to bring the world highest luminosity (L=8x10³⁵/cm²/s). Hence, the KEKB injector linac has to produce low emittance and high charge electron (20 mm mrad, 7 GeV/c², 5 nC) and positron (20 mm mrad, 4 GeV/c², 4 nC) beam, respectively. In order to achieve these criteria, the accelerator structure has to be aligned within 0.1 mm position error. Since BPMs are essential instruments for beam based alignment (BBA), it is required to have one magnitude better position resolution to get enough alignment results. We have begun to develop high position resolution BPM readout system with narrow bandpass filters (fc = 180 MHz) and 250 MSa/s 16-bit ADCs. It handles two bunches with 96 ns interval separately and has a dynamic range from 0.1 nC to 10 nC. To compensate circuit drift, two calibration (x-direction and y-direction) pulses are output to the BPM electrodes between beam cycles (20 ms). Since it needs to achieve not only high position resolution but also good position accuracy, overall non-linearity within ±0.02 dB is required and the system has to have more than ±5 mm accurate position range. We confirmed the system performance with a 3-BPM resolution tests at KEK Injector Linac and it turned out that the system has 3 μm position resolution. We plan to install this system during 2015 summer shutdown.

Poster WEPD04 [0.828 MB]

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