LINAC2014 - List of Authors (Hasegawa, K.)

Paper

Title

Page

Commissioning of Energy Upgraded Linac of J-PARC

417

K. Hasegawa
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

To realize a full potential of J-PARC facility (1MW at 3 GeV), the J-PARC linac is upgraded from 181 MeV to 400 MeV by using an annular-ring coupled structure linac (ACS). The ACS modules and peripheral system were installed and commissioned in summer to autumn of 2013. Beam commissioning is about to start and results will be expected.

Slides TUIOB03 [4.905 MB]

TUPP070

Status and Recent Modifications to 324-MHz RF Source in J-PARC LINAC

587

M. Kawamura, Y. Fukui, K. Futatsukawa, F. Naito
KEK, Ibaraki, Japan
E. Chishiro, K. Hasegawa, F. Sato, S. Shinozaki
JAEA/J-PARC, Tokai-mura, Japan
T. Hori
JAEA, Ibaraki-ken, Japan

This paper describes the present status of and the recent modifications to the 324-MHz RF source in the J-PARC linac. The recovery from the Great East Japan Earthquake Disaster, the status of the 324-MHz klystrons, the failure of 3 high-voltage transformers (HVTRs), and the discharge suppression for the anode-modulators are described.

Poster TUPP070 [0.660 MB]

TUPP073

Study of the ACS Cavity Without a Bridge Cavity

596

TUPOL05

use link to see paper's listing under its alternate paper code

F. Naito, K. Takata
KEK, Ibaraki, Japan
H. Ao, K. Hasegawa, K. Hirano, T. Morishita, N. Ouchi
JAEA/J-PARC, Tokai-mura, Japan

J-PARC has installed the Annular-ring Coupled Structure (ACS) linac to increase the beam energy up to 400 MeV. One ACS module is composed of two accelerating tanks which are coupled by the bridge cavity. The bridge cavity simplifies the handling of the multi-tank system. While it is possible to feed the RF power into the each tanks directly with the power divider and the phase shifter instead of the bridge cavity. The rf properties of the ACS linac with the direct rf-power supply system has been measured by using the low power model made of aluminum. The measured results are described in the paper.

Slides TUPP073 [5.042 MB]

TUPP095

High-Power Test Results of the RFQ III in J-PARC Linac

649

T. Morishita, K. Hasegawa, K. Hirano, Y. Kondo, H. Oguri, S. Yamazaki
JAEA/J-PARC, Tokai-mura, Japan
T. Hori
JAEA, Ibaraki-ken, Japan
F. Naito, T. Sugimura, A. Takagi
KEK, Ibaraki, Japan

The J-PARC accelerator comprises an injector linac, a 3-GeV Rapid-Cycling Synchrotron and a 50-GeV Main Ring. The beam energy of the linac has been upgraded from 181MeV to 400MeV in 2013. For the beam current upgrade, the new frontend (RF ion source, RFQ, chopping system) installation is scheduled in summer 2014 for 1MW operation at RCS. The RFQ III, which is designed for 50mA beam acceleration from 0.05MeV to 3MeV, has been fabricated and the high-power test has started at April 2013 at the test station in the J-PARC. The test station consists of the ion source, the LEBT, the RFQ, and the diagnostics devices. The nominal RF power and RF duty of the RFQ III are 380kW and 3%(0.6ms and 50Hz), respectively. The high-power conditioning reached to the 120% of the nominal power with 1.5% (0.6ms, 25Hz) RF duty within 24 hours. Then, we performed the beam operation at the test station and measured beam parameters after the RFQ III. The results of the high-power conditioning and the stability of the RFQ operation with beam will be discussed.

THPP091

Installation and Performance Check of Beam Monitors for Energy Upgraded J-PARC Linac

1059

A. Miura, K. Hasegawa, H. Oguri, N. Ouchi
JAEA/J-PARC, Tokai-mura, Japan
M. Ikegami
FRIB, East Lansing, Michigan, USA
Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
T. Maruta
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
T. Miyao
KEK, Ibaraki, Japan

An energy upgrade project has started to achieve the design beam power of 1 MW at the exit of the downstream synchrotron in the J-PARC Linac since 2009. In the upgraded project, a beam energy in the Linac has increased from present 181 MeV to 400 MeV using the additional 21 annular-ring coupled structure (ACS) cavities. The new beam monitors as the beam current monitors, the phase monitors, the beam position monitors, the transverse profile monitors (wire scanner monitors) and the longitudinal profile monitors (bunch shape monitors) for the part where the ACS cavities were installed were designed, fabricated and calibrated. Till the end of November, 2013, all beam monitors were completed to be installed. From the middle of December, we started the beam commissioning to achieve the beam energy as 400 MeV, as well as to confirm the beam monitor functioning. We achieved the 400 MeV beam acceleration at the middle of January, 2014 using newly installed beam monitors. This paper describes the beam monitor installation, calibration and the beam commissioning results of beam monitor functioning.

Paper	Title	Page
TUIOB03	Commissioning of Energy Upgraded Linac of J-PARC	417
	K. Hasegawa J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	To realize a full potential of J-PARC facility (1MW at 3 GeV), the J-PARC linac is upgraded from 181 MeV to 400 MeV by using an annular-ring coupled structure linac (ACS). The ACS modules and peripheral system were installed and commissioned in summer to autumn of 2013. Beam commissioning is about to start and results will be expected.
	Slides TUIOB03 [4.905 MB]

TUPP070	Status and Recent Modifications to 324-MHz RF Source in J-PARC LINAC	587
	M. Kawamura, Y. Fukui, K. Futatsukawa, F. Naito KEK, Ibaraki, Japan E. Chishiro, K. Hasegawa, F. Sato, S. Shinozaki JAEA/J-PARC, Tokai-mura, Japan T. Hori JAEA, Ibaraki-ken, Japan
	This paper describes the present status of and the recent modifications to the 324-MHz RF source in the J-PARC linac. The recovery from the Great East Japan Earthquake Disaster, the status of the 324-MHz klystrons, the failure of 3 high-voltage transformers (HVTRs), and the discharge suppression for the anode-modulators are described.
	Poster TUPP070 [0.660 MB]

TUPP073	Study of the ACS Cavity Without a Bridge Cavity	596
TUPOL05	use link to see paper's listing under its alternate paper code
	F. Naito, K. Takata KEK, Ibaraki, Japan H. Ao, K. Hasegawa, K. Hirano, T. Morishita, N. Ouchi JAEA/J-PARC, Tokai-mura, Japan
	J-PARC has installed the Annular-ring Coupled Structure (ACS) linac to increase the beam energy up to 400 MeV. One ACS module is composed of two accelerating tanks which are coupled by the bridge cavity. The bridge cavity simplifies the handling of the multi-tank system. While it is possible to feed the RF power into the each tanks directly with the power divider and the phase shifter instead of the bridge cavity. The rf properties of the ACS linac with the direct rf-power supply system has been measured by using the low power model made of aluminum. The measured results are described in the paper.
	Slides TUPP073 [5.042 MB]

TUPP095	High-Power Test Results of the RFQ III in J-PARC Linac	649
	T. Morishita, K. Hasegawa, K. Hirano, Y. Kondo, H. Oguri, S. Yamazaki JAEA/J-PARC, Tokai-mura, Japan T. Hori JAEA, Ibaraki-ken, Japan F. Naito, T. Sugimura, A. Takagi KEK, Ibaraki, Japan
	The J-PARC accelerator comprises an injector linac, a 3-GeV Rapid-Cycling Synchrotron and a 50-GeV Main Ring. The beam energy of the linac has been upgraded from 181MeV to 400MeV in 2013. For the beam current upgrade, the new frontend (RF ion source, RFQ, chopping system) installation is scheduled in summer 2014 for 1MW operation at RCS. The RFQ III, which is designed for 50mA beam acceleration from 0.05MeV to 3MeV, has been fabricated and the high-power test has started at April 2013 at the test station in the J-PARC. The test station consists of the ion source, the LEBT, the RFQ, and the diagnostics devices. The nominal RF power and RF duty of the RFQ III are 380kW and 3%(0.6ms and 50Hz), respectively. The high-power conditioning reached to the 120% of the nominal power with 1.5% (0.6ms, 25Hz) RF duty within 24 hours. Then, we performed the beam operation at the test station and measured beam parameters after the RFQ III. The results of the high-power conditioning and the stability of the RFQ operation with beam will be discussed.

THPP091	Installation and Performance Check of Beam Monitors for Energy Upgraded J-PARC Linac	1059
	A. Miura, K. Hasegawa, H. Oguri, N. Ouchi JAEA/J-PARC, Tokai-mura, Japan M. Ikegami FRIB, East Lansing, Michigan, USA Y. Liu KEK/JAEA, Ibaraki-Ken, Japan T. Maruta J-PARC, KEK & JAEA, Ibaraki-ken, Japan T. Miyao KEK, Ibaraki, Japan
	An energy upgrade project has started to achieve the design beam power of 1 MW at the exit of the downstream synchrotron in the J-PARC Linac since 2009. In the upgraded project, a beam energy in the Linac has increased from present 181 MeV to 400 MeV using the additional 21 annular-ring coupled structure (ACS) cavities. The new beam monitors as the beam current monitors, the phase monitors, the beam position monitors, the transverse profile monitors (wire scanner monitors) and the longitudinal profile monitors (bunch shape monitors) for the part where the ACS cavities were installed were designed, fabricated and calibrated. Till the end of November, 2013, all beam monitors were completed to be installed. From the middle of December, we started the beam commissioning to achieve the beam energy as 400 MeV, as well as to confirm the beam monitor functioning. We achieved the 400 MeV beam acceleration at the middle of January, 2014 using newly installed beam monitors. This paper describes the beam monitor installation, calibration and the beam commissioning results of beam monitor functioning.