Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 25

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

Design and actual performance of J-PARC 3 GeV rapid cycling synchrotron for high-intensity operation

Yamamoto, Kazami; Kinsho, Michikazu; Hayashi, Naoki; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Tani, Norio; Takayanagi, Tomohiro; Kamiya, Junichiro; Shobuda, Yoshihiro; et al.

Journal of Nuclear Science and Technology, 59(9), p.1174 - 1205, 2022/09

 Times Cited Count:3 Percentile:80.29(Nuclear Science & Technology)

In the Japan Proton Accelerator Research Complex, the purpose of the 3 GeV rapid cycling synchrotron (RCS) is to accelerate a 1 MW, high-intensity proton beam. To achieve beam operation at a repetition rate of 25 Hz at high intensities, the RCS was elaborately designed. After starting the RCS operation, we carefully verified the validity of its design and made certain improvements to establish a reliable operation at higher power as possible. Consequently, we demonstrated beam operation at a high power, namely, 1 MW. We then summarized the design, actual performance, and improvements of the RCS to achieve a 1 MW beam.

Journal Articles

Analysis of machine protection system events in the J-PARC Linac/RCS

Hayashi, Naoki; Hatakeyama, Shuichiro; Fukuta, Shimpei*

Proceedings of 18th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.679 - 682, 2021/10

In order to achieve a high availability in a user facility accelerator complex, it is necessary to understand in detail not only the simple failure cause of the magnet or the acceleration cavity power supply, but also complex interlocked events. At J-PARC, not only the primary interlock information but also the data recorded by the beam diagnostic system before the interlocked event is used to carefully reconstruct the event and clarify the cause more accurately. This time, we proceeded with the analysis based on more detailed waveform of the RCS Beam Loss Monitor and the events during simultaneous operation of MLF and MR. We present various events of the beam destination switching problem, the influence of the ion source discharged, and the events related to the RCS extraction kicker.

Journal Articles

Spallation and fragmentation cross sections for 168 MeV/nucleon $$^{136}$$Xe ions on proton, deuteron, and carbon targets

Sun, X. H.*; Wang, H.*; Otsu, Hideaki*; Sakurai, Hiroyoshi*; Ahn, D. S.*; Aikawa, Masayuki*; Fukuda, Naoki*; Isobe, Tadaaki*; Kawakami, Shunsuke*; Koyama, Shumpei*; et al.

Physical Review C, 101(6), p.064623_1 - 064623_12, 2020/06

 Times Cited Count:5 Percentile:53.56(Physics, Nuclear)

The spallation and fragmentation reactions of $$^{136}$$Xe induced by proton, deuteron and carbon at 168 MeV/nucleon were studied at RIKEN Radioactive Isotope Beam Factory via the inverse kinematics technique. The cross sections of the lighter products are larger in the carbon-induced reactions due to the higher total kinetic energy of carbon. The energy dependence was investigated by comparing the newly obtained data with previous results obtained at higher reaction energies. The experimental data were compared with the results of SPACS, EPAX, PHITS and DEURACS calculations. These data serve as benchmarks for the model calculations.

Journal Articles

How different is the core of $$^{25}$$F from $$^{24}$$O$$_{g.s.}$$ ?

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:74.77(Physics, Multidisciplinary)

The structure of a neutron-rich $$^{25}$$F nucleus is investigated by a quasifree ($$p,2p$$) knockout reaction. The sum of spectroscopic factors of $$pi 0d_{5/2}$$ orbital is found to be 1.0 $$pm$$ 0.3. The result shows that the $$^{24}$$O core of $$^{25}$$F nucleus significantly differs from a free $$^{24}$$O nucleus, and the core consists of $$sim$$35% $$^{24}$$O$$_{rm g.s.}$$, and $$sim$$65% excited $$^{24}$$O. The result shows that the $$^{24}$$O core of $$^{25}$$F nucleus significantly differs from a free $$^{24}$$O nucleus. The result may infer that the addition of the $$0d_{5/2}$$ proton considerably changes the neutron structure in $$^{25}$$F from that in $$^{24}$$O, which could be a possible mechanism responsible for the oxygen dripline anomaly.

Journal Articles

Lattice dynamics in FeSe via inelastic X-ray scattering and first-principles calculations

Murai, Naoki; Fukuda, Tatsuo; Nakajima, Masamichi*; Kawamura, Mitsuaki*; Ishikawa, Daisuke*; Tajima, Setsuko*; Baron, A. Q. R.*

Physical Review B, 101(3), p.035126_1 - 035126_6, 2020/01

 Times Cited Count:5 Percentile:33.73(Materials Science, Multidisciplinary)

We report an inelastic X-ray scattering investigation of phonons in FeSe superconductor. Comparing the experimental phonon dispersion with density functional theory (DFT) calculations in the non-magnetic state, we found a significant disagreement between them. A better overall agreement was obtained by allowing for spin-polarization in DFT calculations, despite the absence of magnetic order in FeSe. This calculation gives a realistic approximation, at DFT level, of the disordered paramagnetic state of FeSe, in which strong spin fluctuations are present.

Journal Articles

Conceptual study on parasitic low-energy RI beam production with in-flight separator BigRIPS and the first stopping examination for high-energy RI beams in the parasitic gas cell

Sonoda, Tetsu*; Katayama, Ichiro*; Wada, Michiharu*; Iimura, Hideki; Sonnenschein, V.*; Iimura, Shun*; Takamine, Aiko*; Rosenbusch, M.*; Kojima, Takao*; Ahn, D. S.*; et al.

Progress of Theoretical and Experimental Physics (Internet), 2019(11), p.113D02_1 - 113D02_12, 2019/11

AA2019-0315.pdf:1.37MB

 Times Cited Count:1 Percentile:11.76(Physics, Multidisciplinary)

An in-flight separator, BigRIPS, at RIBF in RIKEN provides each experiment with specific nuclides separated from many nuclides produced by projectile fragmentation or in-flight fission. In this process, nuclides other than separated ones are discarded on the slits in BigRIPS, although they include many nuclides interested from the view point of nuclear structure. In order to extract these nuclides for parasitic experiments, we are developing a method using laser ion-source (PALIS). A test experiment with $$^{78}$$Se beam from RIBF has been performed by using a gas cell set in BigRIPS. Unstable nuclides around $$^{67}$$Se were stopped in the gas cell in accordance with a calculation using LISE code. The stopping efficiency has been estimated to be about 30%. As a next step, we will establish the technique for extracting reaction products from the gas cell.

Journal Articles

Enhancement of element production by incomplete fusion reaction with weakly bound deuteron

Wang, H.*; Otsu, Hideaki*; Chiga, Nobuyuki*; Kawase, Shoichiro*; Takeuchi, Satoshi*; Sumikama, Toshiyuki*; Koyama, Shumpei*; Sakurai, Hiroyoshi*; Watanabe, Yukinobu*; Nakayama, Shinsuke; et al.

Communications Physics (Internet), 2(1), p.78_1 - 78_6, 2019/07

 Times Cited Count:7 Percentile:56.64(Physics, Multidisciplinary)

Searching for effective pathways for the production of proton- and neutron-rich isotopes through an optimal combination of reaction mechanism and energy is one of the main driving forces behind experimental and theoretical nuclear reaction studies as well as for practical applications in nuclear transmutation of radioactive waste. We report on a study on incomplete fusion induced by deuteron, which contains one proton and one neutron with a weak binding energy and is easily broken up. This reaction study was achieved by measuring directly the cross sections for both proton and deuteron for $$^{107}$$Pd at 50 MeV/u via inverse kinematics technique. The results provide direct experimental evidence for the onset of a cross-section enhancement at high energy, indicating the potential of incomplete fusion induced by loosely-bound nuclei for creating proton-rich isotopes and nuclear transmutation of radioactive waste.

Journal Articles

Effect of magnetism on lattice dynamics in SrFe$$_2$$As$$_2$$ using high-resolution inelastic X-ray scattering

Murai, Naoki*; Fukuda, Tatsuo; Kobayashi, Tatsuya*; Nakajima, Masamichi*; Uchiyama, Hiroshi*; Ishikawa, Daisuke*; Tsutsui, Satoshi*; Nakamura, Hiroki; Machida, Masahiko; Miyasaka, Shigeki*; et al.

Physical Review B, 93(2), p.020301_1 - 020301_5, 2016/01

 Times Cited Count:7 Percentile:34.33(Materials Science, Multidisciplinary)

Journal Articles

Yrast 6$$^+$$ seniority isomers of $$^{136,138}$$Sn

Simpson, G. S.*; Gey, G.*; Jungclaus, A.*; Taprogge, J.*; Nishimura, Shunji*; Sieja, K.*; Doornenbal, P.*; Lorusso, G.*; S$"o$derstr$"o$m, P.-A.*; Sumikama, Toshiyuki*; et al.

Physical Review Letters, 113(13), p.132502_1 - 132502_6, 2014/09

 Times Cited Count:65 Percentile:92.04(Physics, Multidisciplinary)

Journal Articles

Monopole-driven shell evolution below the doubly magic nucleus $$^{132}$$Sn explored with the long-lived isomer in $$^{126}$$Pd

Watanabe, H.*; Lorusso, G.*; Nishimura, Shunji*; Otsuka, T.*; Ogawa, K.*; Xu, Z. Y.*; Sumikama, Toshiyuki*; S$"o$derstr$"o$m, P.-A.*; Doornenbal, P.*; Li, Z.*; et al.

Physical Review Letters, 113(4), p.042502_1 - 042502_6, 2014/07

 Times Cited Count:24 Percentile:77.04(Physics, Multidisciplinary)

Journal Articles

Observation of a $$p$$-wave one-neutron halo configuration on $$^{37}$$Mg

Kobayashi, Nobuyuki*; Nakamura, Takashi*; Kondo, Yosuke*; Tostevin, J. A.*; Utsuno, Yutaka; Aoi, Nori*; Baba, Hidetada*; Barthelemy, R.*; Famiano, M. A.*; Fukuda, Naoki*; et al.

Physical Review Letters, 112(24), p.242501_1 - 242501_5, 2014/06

 Times Cited Count:83 Percentile:94.33(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Deformation-driven $$p$$-wave halos at the drip-line; $$^{31}$$Ne

Nakamura, Takashi*; Kobayashi, Nobuyuki*; Kondo, Yosuke*; Sato, Yoshiteru*; Tostevin, J. A.*; Utsuno, Yutaka; Aoi, Nori*; Baba, Hidetada*; Fukuda, Naoki*; Gibelin, J.*; et al.

Physical Review Letters, 112(14), p.142501_1 - 142501_5, 2014/04

 Times Cited Count:59 Percentile:91.22(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

$$1p_{3/2}$$ proton-hole state in $$^{132}$$Sn and the shell structure along $$N$$=82

Taprogge, J.*; Jungclaus, A.*; Grawe, H.*; Nishimura, Shunji*; Doornenbal, P.*; Lorusso, G.*; Simpson, G.*; S$"o$derstr$"o$m, P.-A.*; Sumikama, Toshiyuki*; Xu, Z. Y.*; et al.

Physical Review Letters, 112(13), p.132501_1 - 132501_6, 2014/04

 Times Cited Count:49 Percentile:88.96(Physics, Multidisciplinary)

Journal Articles

Evidence for a new nuclear "magic number" from the level structure of $$^{54}$$Ca

Steppenbeck, D.*; Takeuchi, Satoshi*; Aoi, Nori*; Doornenbal, P.*; Matsushita, Masafumi*; Wang, H.*; Baba, Hidetada*; Fukuda, Naoki*; Go, Shintaro*; Homma, Michio*; et al.

Nature, 502(7470), p.207 - 210, 2013/10

 Times Cited Count:275 Percentile:99.78(Multidisciplinary Sciences)

no abstracts in English

Journal Articles

Halo structure of the island of inversion nucleus $$^{31}$$Ne

Nakamura, Takashi*; Kobayashi, Nobuyuki*; Kondo, Yosuke*; Sato, Yoshiteru*; Aoi, Nori*; Baba, Hidetada*; Deguchi, Shigeki*; Fukuda, Naoki*; Gibelin, J.*; Inabe, Naoto*; et al.

Physical Review Letters, 103(26), p.262501_1 - 262501_4, 2009/12

 Times Cited Count:192 Percentile:97.52(Physics, Multidisciplinary)

no abstracts in English

Journal Articles

Crystal and magnetic structures and their temperature dependence of Co$$_{2}$$Z-type hexaferrite (Ba, Sr)$$_{3}$$Co$$_{2}$$Fe$$_{24}$$O$$_{41}$$ by high-temperature neutron diffraction

Takada, Yukio*; Nakagawa, Takashi*; Tokunaga, Masatoshi*; Fukuta, Yasunari*; Tanaka, Takayoshi*; Yamamoto, Takao*; Tachibana, Takeshi*; Kawano, Shinji*; Ishii, Yoshinobu; Igawa, Naoki

Journal of Applied Physics, 100(4), p.043904_1 - 043904_7, 2006/08

 Times Cited Count:69 Percentile:89.28(Physics, Applied)

no abstracts in English

Journal Articles

Gamow-Teller decay of the $$T=1$$ nucleus $$^{46}$$Cr

Onishi, Takeo*; Gelberg, A.*; Sakurai, Hiroyoshi*; Yoneda, Kenichiro*; Aoi, Nori*; Imai, Nobuaki*; Baba, Hidetada*; Von Brentano, P.*; Fukuda, Naoki*; Ichikawa, Yuichi*; et al.

Physical Review C, 72(2), p.024308_1 - 024308_7, 2005/08

 Times Cited Count:21 Percentile:77.68(Physics, Nuclear)

no abstracts in English

Journal Articles

Temperature dependence of magnetic moment orientation in Co$$_{2}$$Z-type hexaferrite estimated by high-temperature neutron diffraction

Takada, Yukio*; Nakagawa, Takashi*; Fukuta, Yasunari*; Tokunaga, Masatoshi*; Yamamoto, Takao*; Tachibana, Takeshi*; Kawano, Shinji*; Igawa, Naoki; Ishii, Yoshinobu

Japanese Journal of Applied Physics, 44(5A), p.3151 - 3156, 2005/05

 Times Cited Count:3 Percentile:13.72(Physics, Applied)

We investigated the correlation between the thremomagnetic curve of Co$$_{2}$$Z-Type hexagonal barium ferrite, Ba$$_{3}$$Co$$_{1.8}$$Fe$$_{24.2}$$O$$_{41}$$ and its magnetic moment direction. The thermomagnetic curve shows two significant magnetization slumps at 540K and 680K. High-temperature neutron diffraction experiment and Rietveld analyses indicate that temperature rise from 523 to 573K makes the magnetic moments turn to the c-axis from a direction parallel to the c-plane most significantly.The change in average orientation of the magnetic moments must be induced by the disappearence of the contribution of cobalt to magnetism in this temperature.

Journal Articles

The IRAC code system to calculate activation and transmutation in the TIARA Facility

Tanaka, Susumu; Fukuda, Mitsuhiro; Nishimura, Koichi; Hosono, Masakazu; Watanabe, Hiromasa; Yamano, Naoki*

Journal of Nuclear Science and Technology, 37(Suppl.1), p.840 - 844, 2000/03

no abstracts in English

JAEA Reports

IRACM: A Code system to calculate induced radioactivity produced by ions and neutrons

; Fukuda, Mitsuhiro; ; Watanabe, Hiromasa; Yamano, Naoki*

JAERI-Data/Code 97-019, 91 Pages, 1997/05

JAERI-Data-Code-97-019.pdf:2.58MB

no abstracts in English

25 (Records 1-20 displayed on this page)