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Tamura, Jun; Kondo, Yasuhiro; Yee-Rendon, B.; Meigo, Shinichiro; Maekawa, Fujio; Kako, Eiji*; Umemori, Kensei*; Sakai, Hiroshi*; Domae, Takeshi*
Proceedings of 32nd Linear Accelerator Conference (LINAC 2024) (Internet), p.496 - 498, 2024/10
Tamura, Jun; Kondo, Yasuhiro; Yee-Rendon, B.; Meigo, Shinichiro; Maekawa, Fujio; Kako, Eiji*; Umemori, Kensei*; Sakai, Hiroshi*; Domae, Takeshi*
Journal of Physics; Conference Series, 2687(5), p.052008_1 - 052008_6, 2024/01
Times Cited Count:0 Percentile:0.00(Physics, Atomic, Molecular & Chemical)Tamura, Jun; Kondo, Yasuhiro; Yee-Rendon, B.; Meigo, Shinichiro; Maekawa, Fujio; Kako, Eiji*; Umemori, Kensei*; Sakai, Hiroshi*; Domae, Takeshi*
Proceedings of 31st International Linear Accelerator Conference (LINAC 2022) (Internet), p.180 - 183, 2022/09
The Japan Atomic Energy Agency (JAEA) has proposed an accelerator-driven subcritical system (ADS) to efficiently reduce high-level radioactive waste generated at nuclear power plants. One of the challenging R&D aspects of ADS is the reliability of the accelerator. In preparation for the full-scale design of the CW proton linac for the JAEA-ADS, we are now prototyping a low-beta (around 0.2) single spoke cavity. Since there is no experience in Japan in manufacturing a superconducting spoke cavity, prototyping and performance testing of the cavity is essential to ensure the feasibility of the JAEA-ADS linac. In the Japanese fiscal year 2021, we have started welding cavity parts together. By preliminarily examining the electron beam welding conditions, each press-formed niobium part was joined with a smooth welding bead. At present, we have fabricated the cavity's body part.
Katayama, Ryo*; Kako, Eiji*; Yamaguchi, Seiya*; Michizono, Shinichiro*; Umemori, Kensei*; Kondo, Yasuhiro
Physical Review Accelerators and Beams (Internet), 25(2), p.021601_1 - 021601_18, 2022/02
Times Cited Count:3 Percentile:49.32(Physics, Nuclear)We investigated the feasibility on the application of a superconducting radio frequency (SRF) niobium cavity to an accelerator-based neutron source for boron neutron capture therapy (BNCT). This paper presents a first feasibility study on the application of a SRF niobium cavity to an accelerator-based neutron source for BNCT, assuming that a superconducting radio frequency quadrupole (SC-RFQ) composed of pure bulk niobium at 4.2 K accelerates the proton/deuteron beams to a beryllium or lithium target for the neutron production of BNCT. We evaluated the feasibility on the following three criteria: comparison of the cooling capacity of the refrigerator to the amount of heat, power consumption of AC, and size of the BNCT system. This study demonstrated that the application of the SRF cavity for the rf-linac-based neutron source of BNCT is feasible, and the 2.5 MeV deuteron SC-RFQ and lithium target system is the optimum.
Kondo, Yasuhiro; Harada, Hiroyuki; Kabumoto, Hiroshi; Kamiya, Junichiro; Matsuda, Makoto; Moriya, Katsuhiro; Tamura, Jun; Kako, Eiji*; Domae, Takeshi*; Sakai, Hiroshi*; et al.
Proceedings of 20th International Conference on RF Superconductivity (SRF 2021) (Internet), p.299 - 302, 2021/10
The Japan Atomic Energy Agency (JAEA) tandem booster is one of the pioneering superconducting heavy ion linac in the world. It consists of 40 QWRs with an operation frequency of 130 MHz and , and has potential to accelerate various ions up to Au to 10 MeV/u. The user operation was started in 1994, however, it has been suspended since the Great East Japan Earthquake in 2011. Recently, in addition to the efforts to restart the tandem booster, activities to develop new lower-beta cavities to improve the acceleration efficiency of heavier ions such as Uranium has been launched. In this work, the current status of the design study of the QWRS for the JAEA tandem facility is presented. Electro-magnetic design using simulation code was performed and acceleration gradient of 5.7 MV/m and 6.6 MV/m was obtained for 130-MHz and 65-MHz QWRs, respectively.
Tamura, Jun; Kondo, Yasuhiro; Maekawa, Fujio; Meigo, Shinichiro; Yee-Rendon, B.; Domae, Takeshi*; Kako, Eiji*; Sakai, Hiroshi*; Umemori, Kensei*
Proceedings of 20th International Conference on RF Superconductivity (SRF 2021) (Internet), p.612 - 615, 2021/06
Tamura, Jun; Kondo, Yasuhiro; Yee-Rendon, B.; Meigo, Shinichiro; Maekawa, Fujio; Hasegawa, Kazuo; Kako, Eiji*; Umemori, Kensei*; Sakai, Hiroshi*; Konomi, Taro*
JPS Conference Proceedings (Internet), 33, p.011049_1 - 011049_6, 2021/03
Tamura, Jun; Kondo, Yasuhiro; Yee-Rendon, B.; Meigo, Shinichiro; Maekawa, Fujio; Hasegawa, Kazuo; Kako, Eiji*; Umemori, Kensei*; Sakai, Hiroshi*; Konomi, Taro*
Proceedings of 19th International Conference on RF Superconductivity (SRF 2019) (Internet), p.399 - 402, 2019/11
Sakai, Hiroshi*; Enami, Kazuhiro*; Furuya, Takaaki*; Kako, Eiji*; Kondo, Yoshinari*; Michizono, Shinichiro*; Miura, Takako*; Qiu, F.*; Sato, Masato*; Shinoe, Kenji*; et al.
Proceedings of 56th ICFA Advanced Beam Dynamics Workshop on Energy Recovery Linacs (ERL 2015) (Internet), p.63 - 66, 2015/12
no abstracts in English
Shinoe, Kenji*; Sakai, Hiroshi*; Umemori, Kensei*; Enami, Kazuhiro*; Sawamura, Masaru; Egi, Masato*; Furuya, Takaaki*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.548 - 552, 2015/09
no abstracts in English
Numata, Naoto*; Asakawa, Tomoyuki*; Sakai, Hiroshi*; Umemori, Kensei*; Furuya, Takaaki*; Shinoe, Kenji*; Enami, Kazuhiro*; Egi, Masato*; Sakanaka, Shogo*; Michizono, Shinichiro*; et al.
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.566 - 570, 2015/09
no abstracts in English
Sawamura, Masaru; Umemori, Kensei*; Sakai, Hiroshi*; Shinoe, Kenji*; Furuya, Takaaki*; Enami, Kazuhiro*; Egi, Masato*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.579 - 582, 2015/09
no abstracts in English
Sato, Masato*; Enami, Kazuhiro*; Furuya, Takaaki*; Michizono, Shinichiro*; Miura, Takako*; Qiu, F.*; Sakai, Hiroshi*; Shinoe, Kenji*; Umemori, Kensei*; Sawamura, Masaru; et al.
Proceedings of 5th International Particle Accelerator Conference (IPAC '14) (Internet), p.2531 - 2533, 2014/07
For the main linac of ERL, high loaded Q (QL) operation is desirable to reduce the input generator power. In such operation mode, the suppression of the micophonics is important to stabilize RF amplitude and phase. One of reasons which causes microphonics is mechanical vibration, which changes the cavity frequency. The vibrations of the cavities, the cryomodule and the floor were investigated and compared with the microphnics data taken during cERL operation.
Umemori, Kensei*; Enami, Kazuhiro*; Furuya, Takaaki*; Michizono, Shinichiro*; Miura, Takako*; Qiu, F.*; Sakai, Hiroshi*; Sato, Masato*; Shinoe, Kenji*; Sawamura, Masaru; et al.
Proceedings of 5th International Particle Accelerator Conference (IPAC '14) (Internet), p.2537 - 2539, 2014/07
We developed ERL main linac cryomodule for Compact ERL (cERL) project, which was constructed in KEK. The module includes two 9-cell L-band superconducting cavities. After construction of cERL recirculation loop, beam operation was started. First electron beam successfully passed the main linac cavities. After adjusting beam optics, energy recovery operation was achieved. Main linac cavity was enough stable for ERL beam operation, however, field emission was a problem for long term operation.
Enami, Kazuhiro*; Furuya, Takaaki*; Sakai, Hiroshi*; Sato, Masato*; Shinoe, Kenji*; Umemori, Kensei*; Michizono, Shinichiro*; Miura, Takako*; Qiu, F.*; Arakawa, Dai*; et al.
Proceedings of 5th International Particle Accelerator Conference (IPAC '14) (Internet), p.2534 - 2536, 2014/07
We evaluated a slidejack tuner adopted as compact ERL Main Linac tuner. The tuner compensates the frequency by extending a cavity. Tuning is driven by two system, piezo and slidejack system. Slide-jack mechanism with long stroke drives coarsely piezo adjust precisely and fast. We tested performance of the tuners on operation.
Sakai, Hiroshi*; Enami, Kazuhiro*; Furuya, Takaaki*; Sato, Masato*; Shinoe, Kenji*; Umemori, Kensei*; Sawamura, Masaru; Cenni, E.*; Aoto, Tomohiro*; Hayashi, Kyohei*; et al.
Proceedings of 5th International Particle Accelerator Conference (IPAC '14) (Internet), p.1787 - 1789, 2014/07
Alignment of superconducting cavities is one of the important issues for linear collider and/or future light source like ERL and X-FEL. To measure the cavity displacement under cooling to liquid He temperature more precisely, we newly developed the position monitor based on the measurement of the interference of light between the measurement target and the reference point. We applied this monitor to the main linac cryomodule of Compact ERL (cERL) and successfully measured the displacement during 2 K cooling with the resolution of 10 m.
Enami, Kazuhiro*; Furuya, Takaaki*; Sakai, Hiroshi*; Sato, Masato*; Shinoe, Kenji*; Umemori, Kensei*; Sawamura, Masaru; Cenni, E.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.602 - 604, 2014/06
no abstracts in English
Sato, Masato*; Umemori, Kensei*; Enami, Kazuhiro*; Sakai, Hiroshi*; Shinoe, Kenji*; Furuya, Takaaki*; Sawamura, Masaru; Cenni, E.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.973 - 976, 2014/06
no abstracts in English
Shinoe, Kenji*; Sakai, Hiroshi*; Umemori, Kensei*; Enami, Kazuhiro*; Sato, Masato*; Furuya, Takaaki*; Sawamura, Masaru; Cenni, E.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.950 - 952, 2014/06
no abstracts in English
Sakai, Hiroshi*; Umemori, Kensei*; Enami, Kazuhiro*; Sato, Masato*; Shinoe, Kenji*; Furuya, Takaaki*; Sawamura, Masaru; Cenni, E.*
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.212 - 216, 2014/06
no abstracts in English