DIPAC2011 - List of Keywords (acceleration)

Paper	Title	Other Keywords	Page
MOPD08	Beam Diagnostics in the J-PARC Linac for ACS Upgrade	linac, diagnostics, pick-up, simulation	50
	A. Miura, S. Sato JAEA/J-PARC, Tokai-mura, Japan Z. Igarashi, M. Ikegami, T. Miyao, T. Toyama KEK, Ibaraki, Japan T. Tomisawa JAEA/LINAC, Ibaraki-ken, Japan
	J-PARC had developed the beam diagnostic devices for the current J-PARC linac and has used them since the operation start. J-PARC linac began the energy upgrade project since 2009 and 21 ACS cavities will be installed. In this project, many cavities and related devices are newly installed in the ACS section and its downstream part. Because the beam parameters are updated, new beam diagnostic devices are fabricated and current diagnostic devices are developed. Beam position monitors (BPM) are newly designed and fabricated, based on the computer simulation and bench test. Because the gas proportional BLMs as the current BLM are sensitive to background noise of X-ray emitted from RF cavities, it is difficult to recognize real beam loss. We need to subtract an X-ray noise from the signal from BLM, another candidate BLMs have been tried to measure the beam loss. In addition, the bunch shape monitor for the longitudinal tuning has been developed in the corroboration with the institute for nuclear research, Russia. In this paper, we describe the new developed devices and their development process, especially for beam loss monitor and the developing bunch shape monitor.

MOPD69	Tune Measurements with High Intensity Beams at SIS-18	injection, monitoring, emittance, diagnostics	206
	R. Singh, P. Forck, W. Kaufmann, P. Kowina GSI, Darmstadt, Germany R. Singh TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: This work is supported by DITANET (novel DIagnostic Techniques for future particle Accelerators: A Marie Curie Initial Training NETwork), Project Number ITN-2008-215080 To achieve high current operation close to the space charge limit in a synchrotron, a precise tune measurement during a full accelerating cycle is required. A tune measurement system that was recently commissioned at GSI synchrotron SIS-18 allows for online evaluation of the actual tune. This system consists of three distinct parts; an exciter which provides power to excite coherent betatron oscillations of the beam. The BPM signals thus induced are digitized by fast ADCs at 125 MSa/s and then the post processing electronics integrates the data bunch by bunch to obtain one position value per bunch. Subsequently base band tune is determined by Fourier transformation of the position data. The tune variation during acceleration for various beam conditions was measured using this system and is discussed. A detailed investigation of the incoherent tune shift was conducted with Uranium ion beams at the injection energy of 11.6 MeV/u. The results show the influence of beam current on the tune spectrum. In addition, the effects of the measurement method on the beam emittance and beam losses are discussed.

TUPD64	Test Measurements of a 20 m/s Carbon Wire Beam Scanner	vacuum, controls, simulation, feedback	452
	M. Koujili, J. De Freitas, B. Dehning, J. Emery, J.F. Herranz Alvarez, D. Ramos, M. Sapinski CERN, Geneva, Switzerland Y. Ait Amira UFC, Besançon, France A. Djerdir UTBM, Belfort, France
	This paper presents the design of the actuator for the fast and high accuracy Wire Scanner system. The actuator consists of a rotary brush-less synchronous motor with the permanent magnet rotor installed inside the vacuum chamber and the stator installed outside. The fork, permanent magnet rotor and two angular position sensors are mounted on the same axis and located inside the beam vacuum chamber. The system has to resist a bake-out temperature of 200°C and ionizing radiation up to tenths of kGy/year. Maximum wire travelling speed of 20 m/s and a position measurement accuracy of 4 μm is required. Therefore, the system must avoid generating vibration and electromagnetic interference. A digital feedback controller will allow maximum flexibility for the loop parameters and feeds the 3-phase linear power driver. The performance of the presented design is investigated through simulations and experimental tests.

TUPD74	The Bunch by Bunch Feedback System in J-PARC Main Ring	feedback, injection, kicker, proton	482
	Y. Kurimoto, Y.H. Chin, T. Obina, M. Tobiyama, T. Toyama KEK, Ibaraki, Japan Y. Shobuda JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	We report the current status of the bunch by bunch feedback system for the J-PARC Main Ring. The J-PARC Main Ring is the synchrotron accelerating protons from 3 GeV to 30 GeV. It is normally operating at the intensity of 135 kW. The bunch by bunch feedback system have been developed and used for the normal operation of J-PARC Main Ring. The system aims to reduce the coherent transverse oscillation due to the instabilities or injection errors. It consists of a beam position monitor, a stripline kicker and a signal processing electronics. We've observed the injection error leading to the head-tail oscillation and succeed in damping such kind of oscillations and reducing the beam loss significantly.
	Poster TUPD74 [1.107 MB]

Paper

Title

Other Keywords

Page

MOPD08

Beam Diagnostics in the J-PARC Linac for ACS Upgrade

linac, diagnostics, pick-up, simulation

50

A. Miura, S. Sato
JAEA/J-PARC, Tokai-mura, Japan
Z. Igarashi, M. Ikegami, T. Miyao, T. Toyama
KEK, Ibaraki, Japan
T. Tomisawa
JAEA/LINAC, Ibaraki-ken, Japan

J-PARC had developed the beam diagnostic devices for the current J-PARC linac and has used them since the operation start. J-PARC linac began the energy upgrade project since 2009 and 21 ACS cavities will be installed. In this project, many cavities and related devices are newly installed in the ACS section and its downstream part. Because the beam parameters are updated, new beam diagnostic devices are fabricated and current diagnostic devices are developed. Beam position monitors (BPM) are newly designed and fabricated, based on the computer simulation and bench test. Because the gas proportional BLMs as the current BLM are sensitive to background noise of X-ray emitted from RF cavities, it is difficult to recognize real beam loss. We need to subtract an X-ray noise from the signal from BLM, another candidate BLMs have been tried to measure the beam loss. In addition, the bunch shape monitor for the longitudinal tuning has been developed in the corroboration with the institute for nuclear research, Russia. In this paper, we describe the new developed devices and their development process, especially for beam loss monitor and the developing bunch shape monitor.

MOPD69

Tune Measurements with High Intensity Beams at SIS-18

injection, monitoring, emittance, diagnostics

206

R. Singh, P. Forck, W. Kaufmann, P. Kowina
GSI, Darmstadt, Germany
R. Singh
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: This work is supported by DITANET (novel DIagnostic Techniques for future particle Accelerators: A Marie Curie Initial Training NETwork), Project Number ITN-2008-215080
To achieve high current operation close to the space charge limit in a synchrotron, a precise tune measurement during a full accelerating cycle is required. A tune measurement system that was recently commissioned at GSI synchrotron SIS-18 allows for online evaluation of the actual tune. This system consists of three distinct parts; an exciter which provides power to excite coherent betatron oscillations of the beam. The BPM signals thus induced are digitized by fast ADCs at 125 MSa/s and then the post processing electronics integrates the data bunch by bunch to obtain one position value per bunch. Subsequently base band tune is determined by Fourier transformation of the position data. The tune variation during acceleration for various beam conditions was measured using this system and is discussed. A detailed investigation of the incoherent tune shift was conducted with Uranium ion beams at the injection energy of 11.6 MeV/u. The results show the influence of beam current on the tune spectrum. In addition, the effects of the measurement method on the beam emittance and beam losses are discussed.

TUPD64

Test Measurements of a 20 m/s Carbon Wire Beam Scanner

vacuum, controls, simulation, feedback

452

M. Koujili, J. De Freitas, B. Dehning, J. Emery, J.F. Herranz Alvarez, D. Ramos, M. Sapinski
CERN, Geneva, Switzerland
Y. Ait Amira
UFC, Besançon, France
A. Djerdir
UTBM, Belfort, France

This paper presents the design of the actuator for the fast and high accuracy Wire Scanner system. The actuator consists of a rotary brush-less synchronous motor with the permanent magnet rotor installed inside the vacuum chamber and the stator installed outside. The fork, permanent magnet rotor and two angular position sensors are mounted on the same axis and located inside the beam vacuum chamber. The system has to resist a bake-out temperature of 200°C and ionizing radiation up to tenths of kGy/year. Maximum wire travelling speed of 20 m/s and a position measurement accuracy of 4 μm is required. Therefore, the system must avoid generating vibration and electromagnetic interference. A digital feedback controller will allow maximum flexibility for the loop parameters and feeds the 3-phase linear power driver. The performance of the presented design is investigated through simulations and experimental tests.

TUPD74

The Bunch by Bunch Feedback System in J-PARC Main Ring

feedback, injection, kicker, proton

482

Y. Kurimoto, Y.H. Chin, T. Obina, M. Tobiyama, T. Toyama
KEK, Ibaraki, Japan
Y. Shobuda
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

We report the current status of the bunch by bunch feedback system for the J-PARC Main Ring. The J-PARC Main Ring is the synchrotron accelerating protons from 3 GeV to 30 GeV. It is normally operating at the intensity of 135 kW. The bunch by bunch feedback system have been developed and used for the normal operation of J-PARC Main Ring. The system aims to reduce the coherent transverse oscillation due to the instabilities or injection errors. It consists of a beam position monitor, a stripline kicker and a signal processing electronics. We've observed the injection error leading to the head-tail oscillation and succeed in damping such kind of oscillations and reducing the beam loss significantly.

Poster TUPD74 [1.107 MB]