Low-power proton beam extraction by the bright continuous laser using the 3-MeV negative-hydrogen linac in Japan Proton Accelerator Research Complex

Takei, Hayanori; Tsutsumi, Kazuyoshi*; Meigo, Shinichiro

Journal of Nuclear Science and Technology, 58(5), p.588 - 603, 2021/05

https://doi.org/10.1080/00223131.2020.1848654

The Japan Atomic Energy Agency (JAEA) has designed a Transmutation Physics Experimental Facility (TEF-P) as an experimental facility in the Japan Proton Accelerator Research Complex (J-PARC). The TEF-P is a critical assembly driven by a low-power proton beam, a maximum of 10 W, which is extracted from a high-power beam source, such as 250 kW of 400 MeV proton beam of the J-PARC Linac. To extract such a low-power proton beam from the high-power proton beam, we developed a laser charge exchange (LCE) device and employed its technique, which is one of the non-contact beam extraction techniques. For the proof of performance of the LCE device to the TEF-P, a low-power proton beam was extracted using a negative-hydrogen (H) Linac having an energy of 3 MeV, and a bright continuous laser. Proton beam with the power of 0.57 mW was successfully extracted with a laser stripping efficiency of . These experimental values are in good agreement with the estimated ones.

Status of laser development for laser stripping experiment at J-PARC

Harada, Hiroyuki; Saha, P. K.; Yoneda, Hitoki*; Michine, Yurina*; Fuchi, Aoi*; Sato, Atsushi*; Shibata, Takanori*; Kinsho, Michikazu

Proceedings of 17th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.441 - 445, 2020/09

The high-intensity proton accelerator adopts a charge exchange injection scheme, which injects with exchanging from negative Hydrogen ion to proton by using carbon foil. This scheme is destructive-type method by using the foil and can accumulate high intensity proton beam. However, the uncontrolled beam losses by scattering at the foil and the foil breaking by the beam collision are a key issue of high-intensity proton accelerator. In order to realize higher intensity, new injection scheme of non-destructive type is needed instead of the foil. We newly propose laser stripping injection scheme by using laser pulse. We plan proof of principle experiment at J-PARC and are developing the laser system. In my presentation, we introduce the overview of laser stripping injection scheme and report the status of laser development.

Development of laser system for a proof-of-principle experiment of laser stripping injection

Harada, Hiroyuki; Saha, P. K.; Yoneda, Hitoki*; Michine, Yurina*; Inoue, Shunsuke*; Sato, Atsushi*; Suganuma, Kazuaki; Yamane, Isao*; Kinsho, Michikazu; Irie, Yoshiro*

Proceedings of 15th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.811 - 815, 2018/08

https://www.pasj.jp/web_publish/pasj2018/proceedings/PDF/THP0/THP017.pdf

The high-intensity proton accelerator adopts a charge exchange injection scheme, which injects with exchanging from negative Hydrogen ion to proton by using carbon foil. This scheme can realize high intensity proton beam but the uncontrolled beam losses occur by scattering at the foil. Additionally, the beam collision at the foil may cause the break itself. Therefore, a new injection scheme for higher intensity is needed as an alternative to the foil. We newly propose and develop a laser stripping injection scheme. At the first step, we propose a proof-of-principle (POP) experiment of the scheme in J-PARC and develop a laser system. In this presentation, we will introduce the laser stripping injection scheme and describe an overview of a POP experiment. We will report a current status of the laser system.

Beam extraction by the laser charge exchange method using the 3-MeV LINAC in J-PARC

Takei, Hayanori; Hirano, Koichiro; Tsutsumi, Kazuyoshi; Meigo, Shinichiro

Plasma and Fusion Research (Internet), 13(Sp.1), p.2406012_1 - 2406012_6, 2018/03

http://www.jspf.or.jp/PFR/PDF2018/pfr2018_13-2406012

The Japan Proton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV negative proton (H) beam will be delivered from the J-PARC linac. Since the TEF-P requires a stable proton beam with a power of less than 10 W, a stable and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250 kW. To fulfil this requirement, the Laser Charge Exchange (LCE) method has been developed. To demonstrate the charge exchange of the H, a preliminary LCE experiment was conducted using a linac with energy of 3 MeV in J-PARC. As a result of the experiment, a charge-exchanged H beam with a power of about 8 W equivalent and an accuracy of about 2% was obtained under the J-PARC linac beam condition.

Laser storage ring with high power for realization of laser stripping injection

Harada, Hiroyuki; Yamane, Isao*; Saha, P. K.; Suganuma, Kazuaki; Kinsho, Michikazu; Irie, Yoshiro*; Kato, Shinichi

Proceedings of 14th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.684 - 688, 2017/12

http://www.pasj.jp/web_publish/pasj2017/proceedings/PDF/TUP1/TUP117.pdf

The high-intensity proton accelerator adopts a charge exchange injection scheme, which injects with exchanging from negative Hydrogen ion to proton by using carbon foil. This scheme can realize high intensity proton beam but the uncontrolled beam losses are caused by scattering between beams and the foil. Additionally, the collision may occur the foil beak. Therefore, a new injection scheme for higher intensity is needed as an alternative to the foil. In the J-PARC 3GeV RCS, we newly propose and develop a laser stripping injection scheme. However, it is necessary that laser power is two order higher than latest laser one. To realize this big issue, we develop the laser storage ring, which can provide laser pulse of high repetition rate by recycling one. In this presentation, we will introduce the laser stripping injection scheme and describe the concept of the laser storage ring with high repetition rate and report the current status.

A Feasibility study of H beam extraction technique using YAG laser

Meigo, Shinichiro; Hasegawa, Kazuo; Ikeda, Yujiro; Oigawa, Hiroyuki; Aoki, Nobutada*; Nakagawa, S.*

JAERI-Tech 2002-095, 40 Pages, 2002/12

JAERI-Tech-2002-095.pdf:2.67MB

no abstracts in English

Status of J-PARC Transmutation Experimental Facility Program, 4; Low-power beam extraction by laser

Takei, Hayanori; Hirano, Koichiro; Tsutsumi, Kazuyoshi; Meigo, Shinichiro

no journal, , 

The Japan Proton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV negative proton (H) beam will be delivered from the J-PARC linac. Since the TEF-P requires a stable proton beam with a power of less than 10W, a stable and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250kW. To fulfil this requirement, the Laser Charge Exchange (LCE) method has been developed. To demonstrate the charge exchange of the H, a preliminary LCE experiment was conducted using a linac with energy of 3MeV in J-PARC. As a result of the experiment, a charge-exchanged H beam with a power of about 8W equivalent was obtained under the J-PARC linac beam condition.

A Proof-Of-Principle (POP) experiment for laser stripping injection

Harada, Hiroyuki; Saha, P. K.; Yoneda, Hitoki*; Michine, Yurina*; Fuchi, Aoi*; Sato, Atsushi*; Kinsho, Michikazu

no journal, , 

The high-intensity proton accelerator adopts a charge exchange injection scheme, which injects with exchanging from negative Hydrogen ion to proton by using carbon foil. This scheme can realize high intensity proton beam but the uncontrolled beam losses are caused by scattering between beams and the foil. Additionally, the collision may occur the foil beak. Therefore, a new injection scheme for higher intensity is needed as an alternative to the foil. In the J-PARC, we newly propose a laser stripping injection scheme by using a laser and develop the laser system for a test. In my presentation, we introduce an overview of laser stripping injection and report the status of the development.

Development of high repetitive laser pulse system for charge exchange process of hydrogen beam in J-PARC

Fuchi, Aoi*; Yoneda, Hitoki*; Michine, Yurina*; Harada, Hiroyuki; Saha, P. K.; Sato, Atsushi*; Shibata, Takanori*; Kinsho, Michikazu

no journal, , 

In the J-PARC as high-intensity proton accelerator, beam injection into a synchrotron uses for charge exchange process from hydrogen to proton. For higher intensity beam, we study laser development and POP experiment for charge exchange by using laser. In our method, we consider doppler shift and multi process of electron stripping. Therefore, we are developing high power laser and the 5th harmonics. In order to reduce laser power, we must increase the utilization rate of laser. So, we develop multi-pass cavity and beam shaper. In our presentation, we will report about a status of high-repetition laser and optics devices under developing.

Development of laser system for charge exchange negative hydrogen ion beam in high-intensity proton accelerator

Fuchi, Aoi*; Yoneda, Hitoki*; Michine, Yurina*; Harada, Hiroyuki; Saha, P. K.; Shibata, Takanori*; Kinsho, Michikazu

no journal, , 

In high-intensity proton accelerator, accelerated H beams in linac are injected with charge exchange in the ring by using carbon foil. This scheme is destructive-type method by using the foil and can accumulate high intensity proton beam. However, the uncontrolled beam losses by scattering at the foil and the foil breaking by the beam collision are a key issue of high-intensity proton accelerator in the world. In the J-PARC, we newly propose a laser stripping injection scheme of nondestructive-type method as an alternative to the foil and are under development for a proof-of-principle experiment of the method. We developed laser system and optical cavity and started the first trial of the experiment. As this experimental result, we realized the charge exchange of 0.57% for final goal one of 99%. In our presentation, developed laser system and optics will be explained and we will report first results of the experiment.