Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
Initialising ...
OKondo, Yosuke*; Achouri, N. L.*; Al Falou, H.*; Atar, L.*; Aumann, T.*; Baba, Hidetada*; Boretzky, K.*; Caesar, C.*; Calvet, D.*; Chae, H.*; et al.
Nature, 620(7976), p.965 - 970, 2023/08
Times Cited Count：5 Percentile：92.64(Multidisciplinary Sciences)no abstracts in English
Ne at the transition into the island of inversion; Detailed structure study of NeWang, H.*; Yasuda, Masahiro*; Kondo, Yosuke*; Nakamura, Takashi*; Tostevin, J. A.*; Ogata, Kazuyuki*; Otsuka, Takaharu*; Poves, A.*; Shimizu, Noritaka*; Yoshida, Kazuki; et al.
Physics Letters B, 843, p.138038_1 - 138038_9, 2023/08
Times Cited Count：2 Percentile：68.16(Astronomy & Astrophysics)Detailed 
-ray spectroscopy of the exotic neon isotope Ne has been performed using the one-neutron removal reaction from Ne. Based on an analysis of parallel momentum distributions, a level scheme with spin-parity assignments has been constructed for Ne and the negative-parity states are identified for the first time. The measured partial cross sections and momentum distributions reveal a significant intruder p-wave strength providing evidence of the breakdown of the N = 20 and N = 28 shell gaps. Only a weak, possible f-wave strength was observed to bound final states. Large-scale shell-model calculations with different effective interactions do not reproduce the large p-wave and small f-wave strength observed experimentally, indicating an ongoing challenge for a complete theoretical description of the transition into the island of inversion along the Ne isotopic chain.
F from 
O
?Tang, T. L.*; Uesaka, Tomohiro*; Kawase, Shoichiro; Beaumel, D.*; Dozono, Masanori*; Fujii, Toshihiko*; Fukuda, Naoki*; Fukunaga, Taku*; Galindo-Uribarri, A.*; Hwang, S. H.*; et al.
Physical Review Letters, 124(21), p.212502_1 - 212502_6, 2020/05
Times Cited Count：14 Percentile：74.18(Physics, Multidisciplinary)The structure of a neutron-rich F nucleus is investigated by a quasifree (
) knockout reaction. The sum of spectroscopic factors of 
orbital is found to be 1.0 
0.3. The result shows that the O core of F nucleus significantly differs from a free O nucleus, and the core consists of 
35% O
, and 65% excited O. The result shows that the O core of F nucleus significantly differs from a free O nucleus. The result may infer that the addition of the 
proton considerably changes the neutron structure in F from that in O, which could be a possible mechanism responsible for the oxygen dripline anomaly.
Sasano, Nakashi*; Enomoto, Atsushi*; Hosoi, Yoshio*; Katsumura, Yosuke; Matsumoto, Yoshihisa*; Shiraishi, Kenshiro*; Miyagawa, Kiyoshi*; Igaki, Hiroshi*; Nakagawa, Keiichi*
Journal of Radiation Research, 48(6), p.495 - 503, 2007/11
Times Cited Count：21 Percentile：53.82(Biology)Morishita, Takatoshi; Asano, Hiroyuki; Ito, Takashi; Ueno, Akira; Hasegawa, Kazuo; Naito, Fujio*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Yoshino, Kazuo*; Ikegami, Masanori*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet), p.1523 - 1525, 2007/06
J-PARC linear accelerator components have been installed. The required alignment accuracy in the J-PARC linac is 0.1mm in transverse direction. In the DTL/SDTL section, the fine alignment was carried out by using an optical alignment telescope along with the cavity installation. The displacement of the DTL by the unit tank connection was monitored by a laser tracker to obtain the tolerable displacement between unit tanks. The heights of cavities and magnets were compensated form the unequal ground movement of the linac tunnel. Finally, all the cavities and magnets are aligned within the tolerable alignment error.
Ito, Takashi; Asano, Hiroyuki; Morishita, Takatoshi; Ao, Hiroyuki; Tanaka, Hirokazu*; Naito, Fujio*; Kato, Takao*; Takasaki, Eiichi*
Proceedings of 2007 Particle Accelerator Conference (PAC '07) (Internet), p.1517 - 1519, 2007/06
The high-power conditioning of the three DTL tanks for the J-PARC has been started in October 2006. The design rf peak-power levels for beam acceleration of the tanks are about 1.1MW (DTL1), 1.2MW (DTL2) and 1.0MW (DTL3), respectively. As a result of the conditioning, we have achieved that the rf power levels are about 1.3MW, 1.45MW and 1.23MW of which are 1.2 times the power levels of the desired one (the pulse length is 650
s and the pulse repetition is 25Hz). During the linac beam commissioning, the DTLs can keep the required rf power stable now.
Ito, Takashi; Asano, Hiroyuki; Morishita, Takatoshi; Yamazaki, Yoshishige; Tanaka, Hirokazu*; Naito, Fujio*; Kato, Takao*; Takasaki, Eiichi*
Proceedings of 23rd International Linear Accelerator Conference (LINAC 2006) (CD-ROM), p.740 - 742, 2007/00
For the J-PARC (Japan Proton Accelerator Research Complex) linac, an SDTL (Separated type Drift Tube Linac) is used to accelerate an H
ion beam from 50 MeV to 191 MeV. We have measured the RF characteristics of the SDTL tanks and adjusted the field distribution. The measured Q value was above 90% of an ideal SUPERFISH value. Furthermore the field distribution was adjusted within 1% for all the tanks.
Ito, Takashi; Asano, Hiroyuki; Morishita, Takatoshi; Yamazaki, Yoshishige; Naito, Fujio*; Takasaki, Eiichi*; Yoshino, Kazuo*; Tanaka, Hirokazu*; Kato, Takao*; Kabeya, Zenzaburo*; et al.
Proceedings of 23rd International Linear Accelerator Conference (LINAC 2006) (CD-ROM), p.782 - 784, 2007/00
Three DTL tanks and 32 SDTL tanks for the Japan Proton Accelerator Research Complex (J-PARC) were assembled at KEK site. After the assembling, the high-power conditioning of the DTL1 and 12 SDTL tanks and the beam acceleration test for the DTL1 ware carried out. And then all the DTL and SDTL tanks have to be transported form KEK to JAEA. In order to confirm the effect of the transportation to the drift tube alignment, we measured the displacement of the drift tube positions before and after the transportation by using a prototype cavity. As a result of the test, the measured displacement of the drift tubes by the transportation was less than 0.02mm which is consistent in the measurement accuracy. Based on this result, all the DTL and SDTL tanks were transported form KEK to JAEA.
Morishita, Takatoshi; Asano, Hiroyuki; Ito, Takashi; Ikegami, Masanori*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Naito, Fujio*; Yoshino, Kazuo*
Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan (CD-ROM), p.376 - 378, 2006/00
In the J-PARC Linac, the DTL and the SDTL have been installed. A precise alignment of accelerator components is essential for high quality beam acceleration. Due to the heavy wiring for DTQs, the realignment of DTL cavity requires a long term. Then the DTL/SDTL and the focusing magnets are aligned precisely enough for the beam operation at the installation. The DTL/SDTL alignment accuracy satisfied the requirement, which confirmed by the laser tracker measurement. The floor level of the accelerator tunnel has been measured periodically. The long term motion of accelerator tunnel is quantitatively evaluated since Feb. 2005.
Ito, Takashi; Asano, Hiroyuki*; Morishita, Takatoshi; Kato, Takao*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Yoshino, Kazuo*; Naito, Fujio*
Proceedings of 2nd Annual Meeting of Particle Accelerator Society of Japan and 30th Linear Accelerator Meeting in Japan, p.242 - 244, 2005/07
The third Drift Tube Linac (DTL3) is adopted for 37MeV-50MeV part of high intensity proton linac for Japan Proton Accelerator Research Complex(J-PARC). DTL3 consists of 26 full drift tubes, 2 half drift tubes and 26 post-couplers. As a result of tuning of the accelerating field of the DTL3, the resonant frequency was adjusted to 324MHz and the average accelerating field distribution was adjusted within 1%.
Kondo, Yasuhiro; Akikawa, Hisashi; Anami, Shozo*; Asano, Hiroyuki*; Fukui, Yuji*; Igarashi, Zenei*; Ikegami, Kiyoshi*; Ikegami, Masanori*; Ito, Takashi; Kawamura, Masato*; et al.
Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.156 - 158, 2004/08
A commissioning of the J-PARC linac DTL1 is now under way at KEK. A 30mA H beam was accelerated to 19.7-MeV, and 100% transmission was obtained with a 20-msec-pulse-width and 12.5-Hz-repetition beam. In this paper, present status of the DTL1 commissioning and preliminary results of the commissioning, such as emittance measurements, are presented.
Ito, Takashi; Asano, Hiroyuki*; Morishita, Takatoshi; Kato, Takao*; Takasaki, Eiichi*; Tanaka, Hirokazu*; Naito, Fujio*
Proceedings of 1st Annual Meeting of Particle Accelerator Society of Japan and 29th Linear Accelerator Meeting in Japan, p.344 - 346, 2004/08
no abstracts in English
Kawata, Tomio; Tsuboya, Takao*; Tanabe, Hiromi*; Yoshimura, Kimitaka*; Asano, Eiichi*; Ouchi, Jin*
no journal, ,
no abstracts in English
