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FCC hierarchical martensite transformation under dynamic impact in FeMnAlNiTi alloyLi, C.*; Fang, W.*; Yu, H. Y.*; Peng, T.*; Yao, Z. T.*; Liu, W. G.*; Zhang, X.*; Xu, P. G.; Yin, F.*
Materials Science & Engineering A, 892, p.146096_1 - 146096_11, 2024/02
Times Cited Count：0 Percentile：0.04(Nanoscience & Nanotechnology)Zhang, T.*; Yao, Y.*; Morita, Koji*; Liu, X.*; Liu, W.*; Imaizumi, Yuya; Kamiyama, Kenji
Proceedings of 30th International Conference on Nuclear Engineering (ICONE30) (Internet), 9 Pages, 2023/05
particles generated by residual gas stripping in the Japan Proton Accelerator Research Complex linacTamura, Jun; Futatsukawa, Kenta*; Kondo, Yasuhiro; Liu, Y.*; Miyao, Tomoaki*; Morishita, Takatoshi; Nemoto, Yasuo*; Okabe, Kota; Yoshimoto, Masahiro
Nuclear Instruments and Methods in Physics Research A, 1049, p.168033_1 - 168033_7, 2023/04
Times Cited Count：1 Percentile：72.91(Instruments & Instrumentation)The Japan Proton Accelerator Research Complex (J-PARC) linac is a high-intensity accelerator in which beam loss is a critical issue. In the J-PARC linac, H
beams are accelerated to 191~MeV by a separated drift tube linac (SDTL) and subsequently to 400~MeV by an annular-ring coupled structure (ACS). Because there are more beam loss mechanisms in H linacs than in proton linacs, it is imperative to investigate the beam loss circumstances for beam loss mitigation. Electron-stripping phenomena, which generate uncontrollable H particles, are characteristic beam loss factors of H linacs. To clarify the beam loss causes in the J-PARC linac, a new diagnostic line was installed in the beam transport between the SDTL and ACS. In this diagnostic line, H particles were separated from the H beam, and the intensity profiles of the H particles were successfully measured by horizontally scanning a graphite plate in the range where H particles were distributed. By examining the intensity variation of the H particles with different residual pressure levels, we proved that half of the H particles in the SDTL section are generated by the residual gas stripping in the nominal beam operation of the J-PARC linac.
Yao, Y.*; Cai, R.*; Yang, S.-H.*; Xing, W.*; Ma, Y.*; Mori, Michiyasu; Ji, Y.*; Maekawa, Sadamichi; Xie, X.-C.*; Han, W.*
Physical Review B, 104(10), p.104414_1 - 104414_6, 2021/09
Times Cited Count：2 Percentile：7.92(Materials Science, Multidisciplinary)Otani, Masashi*; Futatsukawa, Kenta*; Miyao, Tomoaki*; Liu, Y.*; Hirano, Koichiro; Kondo, Yasuhiro; Miura, Akihiko; Oguri, Hidetomo
Journal of Physics; Conference Series, 1350, p.012078_1 - 012078_5, 2019/12
Times Cited Count：1 Percentile：52.28(Physics, Particles & Fields)The Japan Proton Accelerator Research Complex (J-PARC) linac is operated with design peak current of 50 mA from 2018. For operation with such a high beam current, itis important to understand transverse and longitudinal beam properties especially in low-velocity region. A medium energy beam transport (MEBT1) line between the 3-MeV radio-frequency quadrupole linac (RFQ) and the 50-MeV drift-tube linac (DTL) is a 3-m-long transport line to match the beam to the DTL and produce a macro pulse configuration for a 3-GeV rapid-cycling synchrotron (RCS). In this paper, recent measurements and beam tuning results in MEBT1 will be presented.
Tang, C.*; Song, Q.*; Chang, C.-Z.*; Xu, Y.*; Onuma, Yuichi; Matsuo, Mamoru*; Liu, Y.*; Yuan, W.*; Yao, Y.*; Moodera, J. S.*; et al.
Science Advances (Internet), 4(6), p.eaas8660_1 - eaas8660_6, 2018/06
Times Cited Count：30 Percentile：84.42(Multidisciplinary Sciences)Miura, Akihiko; Liu, Y.*; Maruta, Tomofumi*; Miyao, Tomoaki*
Proceedings of 5th International Beam Instrumentation Conference (IBIC 2016) (Internet), p.150 - 153, 2017/03
no abstracts in English
Miyao, Tomoaki*; Maruta, Tomofumi*; Liu, Y.*; Miura, Akihiko
Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1094 - 1096, 2016/11
no abstracts in English
Miura, Akihiko; Hayashi, Naoki; Maruta, Tomofumi*; Liu, Y.*; Miyao, Tomoaki*; Fukuoka, Shota*
Proceedings of 4th International Beam Instrumentation Conference (IBIC 2015) (Internet), p.386 - 389, 2016/02
We have used bunch shape monitors (BSMs) to measure the longitudinal bunch length of negative hydrogen ion beam in the J-PARC linac. In order to evaluate the measurement errors with peak beam current increasing, we observed waveforms with various beam current. As the result, an RMS bunch length depends on the peak beam current and the bending at the pulse head grows with the peak beam current. We also compared the data taken at an off-center beam to avoid the thermal stress with the ones at an on-center beam, because a target wire will be exposed to a higher peak beam current. In this paper, we introduced the peak beam current dependence of the bunch length waveforms, and an effect of on- /off-centering of the wire position. Finally the new buncher tuning method using one BSM have been discussed.
Miura, Akihiko; Maruta, Tomofumi*; Liu, Y.*; Miyao, Tomoaki*; Kawane, Yusuke; Ouchi, Nobuo; Oguri, Hidetomo; Ikegami, Masanori*; Hasegawa, Kazuo
JPS Conference Proceedings (Internet), 8, p.011002_1 - 011002_6, 2015/09
In the J-PARC Linac, an energy upgrade project has started since 2009 using Annular-ring Coupled Structure cavities to achieve design beam power of 1 MW at the exit of the downstream rapid cycling synchrotron. Linac beam parameters of the upgraded Linac is drastically improved especially for the beam energy from 181 to 400 MeV in the project. To meet with the significant upgrades of the Linac, beam monitors to be used for the upgraded beam line are newly designed and fabricated as well as the beam monitor layout is designed with the consideration to the beam commissioning strategies. This paper introduces the beam monitor layout in the new beam line and the commissioning results to confirm the beam monitor functioning.
Miura, Akihiko; Feschenko, A. V.*; Mirzojan, A. N.*; Miyao, Tomoaki*; Ouchi, Nobuo; Maruta, Tomofumi*; Liu, Y.*; Oguri, Hidetomo; Ikegami, Masanori*; Hasegawa, Kazuo
JPS Conference Proceedings (Internet), 8, p.011003_1 - 011003_6, 2015/09
In J-PARC Linac, an energy upgrade project has started since 2009 using Annular-ring Coupled Structure (ACS) cavities. We have decided to use the bunch shape monitors (BSM) as the monitors of the longitudinal beam width measurement in order to take the longitudinal matching using two bunchers located in the upstream of ACS cavities, where the RF frequency jumps from 324 to 972 MHz. Three BSMs were completely fabricated and installed in the beam line. The BSMs were commissioned with the beam and their operability was demonstrated. We found the vacuum degradation during the measurement. We once removed all BSMs to have a vacuum conditioning and postponed the longitudinal matching at the establishment of 400-MeV operation of the energy upgraded Linac. In this paper, we introduce the mechanism of the BSM, its operability, the measurement results with the 181 MeV beam and consistency check with the respect cavity amplitude. We also describe the operational vacuum conditions and the outline of the improvement of the vacuum system for the BSMs.
Sawabe, Yuki; Maruta, Tomofumi*; Liu, Y.*; Miura, Akihiko; Miyao, Tomoaki*; Ishiyama, Tatsuya; Kikuzawa, Nobuhiro; Hayashi, Naoki
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1202 - 1205, 2015/09
no abstracts in English
Maruta, Tomofumi*; Liu, Y.*; Futatsukawa, Kenta*; Miyao, Tomoaki*; Miura, Akihiko; Ikegami, Masanori*
Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.432 - 436, 2015/09
no abstracts in English
Miura, Akihiko; Ouchi, Nobuo; Oguri, Hidetomo; Hasegawa, Kazuo; Maruta, Tomofumi*; Liu, Y.*; Miyao, Tomoaki*; Ikegami, Masanori*
Proceedings of 27th International Linear Accelerator Conference (LINAC 2014) (Internet), p.1059 - 1061, 2014/12
An energy upgrade project has started in the J-PARC Linac since 2009. In the upgraded project, beam energy in the Linac has increased from original 181 MeV to 400 MeV using the additional 21 Annular-ring Coupled Structure Linac (ACS) cavities. The new beam monitors as the beam current monitors, the phase monitors, the beam position monitors and the transverse profile monitors (wire scanner monitors) were designed and fabricated. By the end of November, 2013, all beam monitors were completely 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 and the beam commissioning results of beam monitor functioning.
Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.
Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10
no abstracts in English
Futatsukawa, Kenta*; Ikegami, Masanori*; Ito, Yuichi; Kikuzawa, Nobuhiro; Sato, Fumiaki; Shinozaki, Shinichi; Suzuki, Takahiro*; Chishiro, Etsuji; Hirano, Koichiro; Fang, Z.*; et al.
Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1149 - 1153, 2014/06
no abstracts in English
Maruta, Tomofumi; Miura, Akihiko; Sako, Hiroyuki; Tamura, Jun; Ikegami, Masanori*; Futatsukawa, Kenta*; Fang, Z.*; Miyao, Tomoaki*; Liu, Y.*
Journal of the Korean Physical Society, 63(7), p.1274 - 1279, 2013/10
Times Cited Count：0 Percentile：0(Physics, Multidisciplinary)Ikegami, Masanori*; Fang, Z.*; Futatsukawa, Kenta*; Miyao, Tomoaki*; Liu, Y.*; Maruta, Tomofumi; Sako, Hiroyuki; Miura, Akihiko; Tamura, Jun; Wei, G.
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.64 - 67, 2013/08
Aoki, Kazuhiro; Seshimo, Kazuyoshi; Guglielmi, Y.*; Nussbaum, C.*; Shimamoto, Toshihiko*; Ma, S.*; Yao, L.*; Kametaka, Masao*; Sakai, Toru*
no journal, ,
Aoki, Kazuhiro; Seshimo, Kazuyoshi; Nussbaum, C.*; Guglielmi, Y.*; Shimamoto, Toshihiko*; Sakai, Toru*; Kametaka, Masao*; Ma, S.*; Yao, L.*
no journal, ,
In order to contribute to the Fault Slip experiment, JAEA has performed friction experiment of borehole cores of the measured interval using a rotary-shear low to high-velocity friction apparatus at Institute of Geology, China Earthquake Administration. Friction experiments were done either dry with room humidity or with 30wt% of H
O, at a normal stress of 1.4 and 4.0 MPa and at low to intermediate slip rates ranging 0.21 microns/s to 2.1mm/s. Cylindrical specimens of Ti-Al-V alloy with 40 mm in diameter were used as rotary and stationary pistons and the alloy pistons exhibit similar behaviors as host rock specimens.
Yao, Y.*; Zhang, T.*; Morita, Koji*; Liu, X.*; Liu, W.*; Imaizumi, Yuya; Kamiyama, Kenji
no journal, ,
