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O(
He,
)F reaction; Identification of the low-energy "super" -Gamow-Teller stateFujita, Hirohiko*; Fujita, Yoshitaka*; Utsuno, Yutaka; Yoshida, Kenichi*; Adachi, Tatsuya*; Algora, A.*; Csatl
s, M.*; Deaven, J. M.*; Estevez-Aguado, E.*; Guess, C. J.*; et al.
Physical Review C, 100(3), p.034618_1 - 034618_13, 2019/09
Times Cited Count：12 Percentile：77.09(Physics, Nuclear)no abstracts in English
Watanabe, Yasuhiro; Tani, Norio; Adachi, Toshikazu*; Someya, Hirohiko*; Irie, Yoshiro*
Proceedings of 9th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.538 - 540, 2012/08
Rapid cycling magnets are excited using a resonant circuit and the current waveform is a DC-biased sinusoidal pattern. However, non-linear characteristic of the magnet produces harmonic components in the magnetic field. The harmonic components are different for each type of magnet depending upon the degree of saturation, and it causes a tracking error. This paper proposes harmonic current control in the resonant circuit to reduce harmonic components in the magnetic field.
Watanabe, Yasuhiro; Tani, Norio; Adachi, Toshikazu*; Igarashi, Susumu*; Someya, Hirohiko*
Proceedings of 1st International Particle Accelerator Conference (IPAC '10) (Internet), p.3242 - 3244, 2010/05
In the J-PARC 3 GeV synchrotron, the horizontal closed-orbit-distortion (COD) variation was observed at first of beam commissioning. The COD correction was very difficult to archive because the beam orbit of each shot changes periodically at a period of about 140 seconds. This paper clarifies that the horizontal COD is caused by the switching noise of the dipole magnet power supply and the periodic variation of the beam orbit is caused by the phase sweep of 1 kHz component that include switching noise. Moreover, it has been demonstrate that the dipole magnet power supply using the improved Pulse Width Modulation (PWM) circuit with a synchronized timing system of the accelerator has successfully suppressed the beam orbit variation.
Tani, Norio; Watanabe, Yasuhiro; Adachi, Toshikazu*; Someya, Hirohiko*; Igarashi, Susumu*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.415 - 417, 2006/00
no abstracts in English
Watanabe, Yasuhiro; Tani, Norio; Adachi, Toshikazu*; Igarashi, Susumu*; Someya, Hirohiko*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.424 - 426, 2006/00
no abstracts in English
Haga, Koichi; Tani, Norio; Watanabe, Yasuhiro; Someya, Hirohiko*; Adachi, Toshikazu*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.418 - 420, 2006/00
no abstracts in English
Oku, Takayuki; Suzuki, Junichi; Sasao, Hajime*; Yamada, Satoru; Furusaka, Michihiro*; Adachi, Tomohiro*; Shinohara, Takenao*; Ikeda, Kazuaki*; Shimizu, Hirohiko
Physica B; Condensed Matter, 356(1-4), p.126 - 130, 2005/02
Times Cited Count：11 Percentile：45.47(Physics, Condensed Matter)We have developed a magnetic neutron lens (MNL) based on a sextupole magnet. A neutron beam, which is incident to the sextupole magnet, either converges or diverges depending on the neutron spin state. Small-angle neutron scattering in focusing geometry (FSANS) was proposed to improve the q-resolution and/or measuring efficiency. The MNL is considered to be the most suitable focusing device for FSANS experiments using a polarized neutron beam, since it focuses the polarized neutron beam free from neutron attenuation and scattering by substances. Recently, we have developed the MNLs with sufficiently large apertures and strong focusing power for FSANS experiments. In this study, we evaluate the focusing property of the MNLs for the polarized neutron beam, and performed FSANS experiments using the MNL. The obtained results are discussed.
Suzuki, Junichi; Oku, Takayuki; Adachi, Tomohiro*; Shimizu, Hirohiko; Kiyanagi, Yoshiaki*; Kamiyama, Takashi*; Hiraga, Fujio*; Iwasa, Hirokatsu*; Sato, Koichi*; Furusaka, Michihiro*
Nuclear Instruments and Methods in Physics Research A, 529(1-3), p.120 - 124, 2004/08
Times Cited Count：11 Percentile：58.51(Instruments & Instrumentation)no abstracts in English
Oku, Takayuki; Suzuki, Junichi; Sasao, Hajime*; Adachi, Tomohiro*; Shinohara, Takenao*; Ikeda, Kazuaki*; Morishima, Takahiro*; Sakai, Kenji*; Kiyanagi, Yoshiaki*; Furusaka, Michihiro*; et al.
Nuclear Instruments and Methods in Physics Research A, 529(1-3), p.116 - 119, 2004/08
Times Cited Count：21 Percentile：77.78(Instruments & Instrumentation)As a neutron has a magnetic dipole moment, it is accelerated in a magnetic field gradient. Thus, we can control a neutron trajectory free from neutron beam attenuation and scattering using the magnetic field gradient. A sextupole magnetic field functions as a neutron focusing and defocusing lens depending on the neutron spin state. The neutron focusing effect was experimentally verified using a 6-piece permanent sextupole magnet. For the application in practical neutron scattering experiments, a sextupole magnet with a sufficiently large aperture accompanied with strong focusing power is demanded. Recently, a superconducting sextupole magnet, a Halbach-type permanent sextupole magnet and a sextupole pulse electro-magnet have been developed in a project of the development and application of neutron optics. These magnets will be dedicated to practical uses in neutron scattering experiments. In this paper, current status of the development of the magnetic neutron lenses is reported, and their application in the neutron scattering experiments is discussed.
and ZnFYamamoto, Tomoyuki*; Mizoguchi, Teruyasu*; Tatsumi, Kazuyoshi*; Tanaka, Isao*; Adachi, Hirohiko*; Muramatsu, Yasuji; Gullikson, E. M.*; Perera, R. C. C.*
Materials Transactions, 45(7), p.1991 - 1993, 2004/07
Times Cited Count：7 Percentile：44.68(Materials Science, Multidisciplinary)First principles calculations have been carried out to investigate the core-hole effects on the theoretical fine structures of the X-ray absorption spectra of MgF and ZnF ath FK-edge. Experimental profiles of the near-edge X-ray absorption fine structures are well reproduced by the theoretical calculations when the core-hole effect is introduced. The dependence of supercell size on the theoretical fine structures is also examined.
Tani, Norio; Adachi, Toshikazu*; Igarashi, Susumu*; Watanabe, Yasuhiro; Someya, Hirohiko*; Sato, Hikaru*; Kishiro, Junichi
IEEE Transactions on Applied Superconductivity, 14(2), p.409 - 412, 2004/06
Times Cited Count：17 Percentile：61.57The 3-GeV synchrotron proposed in the JAERI/KEK Joint Project (J-PARC) is a rapid-cycling synchrotron (RCS), which accelerates a high-intensity proton beam from 400-MeV to 3-GeV at a repetition rate of 25-Hz. The 3-GeV synchrotron is used to produce pulsed spallation neutrons and muons. It also works as an injector for a 50-GeV synchrotron. The 3-GeV synchrotron consists of 24 dipole magnets, 60 quadrupole magnets, 18 sextupole magnets and 52 steering magnets. Since the magnets for the 3-GeV synchrotron are required to have a large aperture in order to realize the large beam power of 1 MW, there is a larger fringe field at a pole end than a usual synchrotron magnet. Therefore, it is important to estimate the magnetic field and the effect of multipole component at the fringe field. In this paper, we report the results of the field calculation and mechanical design of RCS magnets.
Tani, Norio; Adachi, Toshikazu*; Someya, Hirohiko*; Watanabe, Yasuhiro; Sato, Hikaru*; Kishiro, Junichi
IEEE Transactions on Applied Superconductivity, 14(2), p.421 - 424, 2004/06
Times Cited Count：13 Percentile：54.64The 3-GeV synchrotron proposed in the JAERI/KEK Joint Project (J-PARC) is a rapid-cycling synchrotron (RCS), which accelerates a high-intensity proton beam from 400-MeV to 3-GeV at a repetition rate of 25-Hz. The 3-GeV synchrotron is used to produce pulsed spallation neutrons and muons. Since the magnets for the 3-GeV synchrotron are required to have a large aperture in order to realize the large beam power of 1 MW, there is a larger fringe field at a pole end than a usual synchrotron magnet. In addition, 25-Hz ac field induces an eddy current in magnet components, magnet end plates and etc. The eddy current induced in the end plates is expected to be large. Therefore, it is important to investigate an effect of large leakage field and eddy current to the beam motion around the magnet end part. We have measured the eddy loss and the eddy field at the edges of the dipole and quadrupole magnets. In this paper, we report the comparison between the results of the measurements and the two-dimensional eddy current model developed for this study.
Oku, Takayuki*; Sakai, Kenji*; Adachi, Tomohiro*; Ikeda, Kazuaki*; Shimizu, Hirohiko*; Maruyama, Ryuji*; Hino, Masahiro*; Tasaki, Seiji*; Kiyanagi, Yoshiaki*; Kamiyama, Takashi*; et al.
Physica B; Condensed Matter, 335(1-4), p.226 - 229, 2003/07
Times Cited Count：7 Percentile：39.38(Physics, Condensed Matter)no abstracts in English
Suzuki, Junichi; Oku, Takayuki*; Adachi, Tomohiro*; Shimizu, Hirohiko*; Hirumachi, Tamiko*; Tsuchihashi, Takahiro*; Watanabe, Ikuo*
Journal of Applied Crystallography, 36(Part3, 1), p.795 - 799, 2003/01
no abstracts in English
Zhang, F.; Watanabe, Yasuhiro; Koseki, Shoichiro*; Tani, Norio; Adachi, Toshikazu*; Someya, Hirohiko*
JAERI-Tech 2002-039, 21 Pages, 2002/03
The 3 GeV Proton RCS of the JAERI-KEK Joint Project is a 25 Hz separate-function rapid cycling synchrotron under design. Bending magnets (BM) and quadrupole magnets (QM) are excited separately. The 3 GeV RCS requests above 10 families of magnets excited independently, far beyond 3 families in practical RCS's. Difficulty of field tracking between BM and QM is significantly increased Magnet strings are grouped into resonant networks and excited resonantly by power supplies driven by a waveform pattern, typically a DC-biased sinusoidal signal. To achieve a close tracking between many families, the driving signal of each power supply should be adjusted in phase and amplitude flexibly and dynamically.This report proposes a signal generator based on VXIbus. The VXIbus, an extension of VMEbus (VME eXtension for Instrument), provides an open architecture with shared process bus and timing. The VXIbus-based signal generator facilitates the timing synchronization and extension to many channels needed by the 3 GeV RCS. Experimental results of the signal generator are reported.
Tani, Norio; Kanazawa, Kenichiro; Shimada, Taihei; Suzuki, Hiromitsu; Watanabe, Yasuhiro; Adachi, Toshikazu*; Someya, Hirohiko*
Proceedings of 8th European Particle Accelerator Conference (EPAC 2002), p.2376 - 2378, 2002/00
The 3-GeV synchrotron proposed in the JAERI/KEK Joint Project is a rapid-cycling synchrotron (RCS), which accelerates a high-intensity proton beam from 400 MeV to 3 GeV at a repetition rate of 25 Hz. The 3-GeV synchrotron is used to produce pulsed spallation neutrons and muons. It also works as an injector for a 50-GeV synchrotron. Since the magnets for the 3-GeV synchrotron are required to have a large aperture in order to realize the large beam power of 1 MW, there is a large leakage field at an end part than a usual synchrotron magnet. In addition, 25-Hz ac field induces an eddy current in magnet components: e.g. a coil, magnet end plates and etc. We intend to use a stranded conductor as a coil conductor so that the eddy current induced in the coil can be reduced. On the other hand, the eddy current induced in the end plates is expected to be large. Therefore, it is important to investigate an effect of the large leakage field and the eddy current to the beam motion around the magnet end part. We have constructed a prototype dipole magnet and field measurement system for this purpose. This paper reports the results of the design and the preliminary test about this magnet.
Koseki, Shoichiro*; Zhang, F.; Watanabe, Yasuhiro; Tani, Norio; Adachi, Toshikazu*; Someya, Hirohiko*
Heisei-13-Nen Denki Gakkai Sangyo Oyo Bumon Zenkoku Taikai Koen Rombunshu, 1, p.253 - 256, 2001/08
no abstracts in English
Watanabe, Yasuhiro; Zhang, F.; Koseki, Shoichiro*; Tani, Norio; Adachi, Toshikazu*; Someya, Hirohiko*
Heisei-13-Nen Denki Gakkai Sangyo Oyo Bumon Zenkoku Taikai Koen Rombunshu, 2, p.761 - 762, 2001/08
no abstracts in English
Hayashi, Takashi; Chino, Masamichi; Yamazawa, Hiromi; Nagai, Haruyasu; Moriuchi, Shigeru*; Ishikawa, Hirohiko*; Adachi, Takashi*; Kojima, Hiromi*; Okano, Hiroshi*; Odagawa, Fumiaki*; et al.
JAERI-Tech 2001-034, 137 Pages, 2001/06
no abstracts in English
Oku, Takayuki*; *; *; Yamagata, Yutaka*; Omori, Hitoshi*; Adachi, Tomohiro*; Shimizu, Hirohiko*; *; Hirota, T.*; Iwasa, Hirokatsu*; et al.
JAERI-Conf 2001-002, p.537 - 541, 2001/03
no abstracts in English
