Papers - AKIMUNE Hidetoshi
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t + $^{3}$He molecular structures in $^{6}$Li studied by ($^{3}$He, $\alpha$) reaction at 450 MeV Reviewed
S. Nakayama, T. Yamagata, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, K. Hashimoto, K. Ichihara, K. Kawase, Y. Matsui, K. Nakanishi, M. Sakama, M. Tanaka, M. Yosoi
Nucl.Phys. A731 355 2004.11
Joint Work
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Tri-nucleon cluster-states in $^{6}$Li Reviewed
S. Nakayama, T. Yamagata, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, H. Hashimoto, K. Ichihara, K. Kawase, Y. Matsui, K. Nakanishi, M. Sakama, M. Tanaka, M. Yosoi
Nucl.Phys. A734 461 2004.11
Joint Work
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Trinucleon cluster structures in $^{6}$Li Reviewed
S. Nakayama, T. Yamagata, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, H. Hashimoto, K. Ichihara, K. Kawase, H. Matsui, K. Nakanishi, M. Sakama, M. Tanaka, M. Yosoi
Phys.Rev. C 69 41304 2004.11
Joint Work
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Systematics of the bimodal isoscalar giant dipole resonance Reviewed
M. Uchida, H. Sakaguchi, M. Itoh, M. Yosoi, T. Kawabata, Y. Yasuda, H. Takeda, T. Murakami, S. Terashima, S. Kishi, U. Garg, P. Boutachkov, M. Hedden, B. Kharraja, M. Koss, B. K. Nayak, S. Zhu, M. Fujiwara, H. Fujimura, H. P. Yoshida, K. Hara, H. Akimune, M. N. Harakeh
Phys.Rev. C 69 51301 2004.11
Joint Work
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Photonuclear reaction studies at synchrotron radiation facilities in Japan Reviewed
H. Utsunomiya, K. Y. Hara, S. Goko, H. Akimune, T. Yamagata, M. Ohta, H. Ohgaki, H. Toyokawa, T. Hayakawa, T. Shizuma, P. Mohr, Y. -W. Lui, H. Ohkuma, H. Yonehara, K. Soutome, M. Arnould
Nucl.Phys. A738 136 2004.11
Joint Work
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Excitations of the $\alpha$ cluster in A = 6 and 7 nuclei Reviewed
T. Yamagata, S. Nakayama, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, H. Hashimoto, K. Ichihara, K. Kawase, M. Kinoshita, Y. Matsui, K. Nakanishi, M. Tanaka, H. Utsunomiya, M. Yosoi
Phys.Rev. C 69 44313 2004.11
Joint Work
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Giant dipole resonances and the analogs of $\alpha$-clusters in A=6 and 7 nuclei Reviewed
T. Yamagata, S. Nakayama, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, K. Hashimoto, K. Ichihara, K. Kawase, M. Kinoshita, Y. Matsui, K. Nakanishi, M. Tanaka, H. Utsunomiya, M. Yosoi
Nucl.Phys. A738 467 2004.11
Joint Work
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Cluster fragmentations of deep (1s)-hole states in light nuclei Reviewed
M. Yosoi, H. Akimune, I. Daito, H. Ejiri, H. Fujimura, M. Fujiwara, K. Fushimi, K. Hara, K. Y. Hara, H. Hashimoto, T. Ishikawa, M. Itoh, Y. Itow, S. Kishi, T. Kawabata, K. Kawase, M. Kinoshita, K. Kobayashi, M. Nakamura, K. Nakanishi, Y. Nakatsugawa, S. Nakayama, T. Noro, E. Obayashi, S. Okumura, H. Sakaguchi, Y. Sakemi, M. Shiozawa, H. Takeda, T. Taki, A. Tamii, M. Tanaka, S. Terashima, H. Toyokawa, N. Tsukahara, M. Uchida, T. Yamada, T. Yamagata, Y. Yasuda, H. P. Yoshida, R. G. T. Zegers, J. Zenihiro
Nucl.Phys. A738 451 2004.11
Joint Work
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Structures and Decay of Deep-Hole States in Light Nuclei Populated by the (p, 2p) Reactions Reviewed
M. Yosoi, H. Akimune, I. Daito, H. Ejiri, H. Fujimura, M. Fujiwara, K. Hara, K. Y. Hara, T. Ishikawa, M. Itoh, Y. Itow, T. Kawabata, K. Kobayashi, M. Nakamura, T. Noro, E. Obayashi, H. Sakaguchi, Y. Sakemi, M. Shiozawa, H. Takeda, T. Taki, A. Tamii, H. Toyokawa, N. Tsukahara, M. Uchida, T. Yamada, Y. Yasuda, H. P. Yoshida, R. G. T. Zegers
Yad.Fiz. 67 1838 2004.11
Joint Work
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Tri-nucleon cluster-states in 6Li
S Nakayama, T Yamagata, H Akimune, M Fujiwara, K Fushimi, MB Greenfield, K Hara, KY Hara, H Hashimoto, K Ichihara, K Kawase, Y Matsui, K Nakanishi, M Sakama, M Tanaka, M Yosoi
Nucl.Phys. A 734 461 2004.11
Joint Work
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Structures and Decay of Deep-Hole States in Light Nuclei Populated by the (p, 2p) Reactions
M. Yosoi, H. Akimune, I. Daito, H. Ejiri, H. Fujimura, M. Fujiwara, K. Hara, K. Y. Hara, T. Ishikawa, M. Itoh, Y. Itow, T. Kawabata, K. Kobayashi, M. Nakamura, T. Noro, E. Obayashi, H. Sakaguchi, Y. Sakemi, M. Shiozawa, H. Takeda, T. Taki, A. Tamii, H. Toyokawa, N. Tsukahara, M. Uchida, T. Yamada, Y. Yasuda, H. P. Yoshida, R. G. T. Zegers
Yad.Fiz. 67 ( 10 ) 1838 - 1817 2004.11
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Trinucleon cluster structure at high-excitation energies in A = 6 nuclei
H. Akimune, T. Yamagata, S. Nakayama, M. Fujiwara, K. Fushimi, K. Hara, K. Y. Hara, K. Ichihara, K. Kawase, K. Matsui, K. Nakanishi, A. Shiokawa, M. Tanaka, H. Utsunomiya, M. Yosoi
Physics of Atomic Nuclei 67 ( 9 ) 1721 - 1725 2004.9
Joint Work
Trinucleon molecular structures in 6He and 6Be were investigated by using the 6Li(7Li, 7Be) 6He reaction at 455 MeV and 6Li(3He, t) 6Be reaction at 450 MeV, respectively. Binary decays into t + t from a broad state at Ex = 18.0 ± 1.0 MeV in 6He and into 3He + 3He from one at Ex = 18.0 ± 1.2 MeV in 6Be, respectively, were observed by measuring trinucleon cluster decays in coincidence with reaction particles. The branching ratios for binary decay were estimated to be about 0.7 for 6He and 6Be. These large branching ratios show that a trinucleon cluster state exists as an isobaric partner around Ex = 18 MeV in 6He and 6Be. © 2004 MAIK "Nauka/ Interperiodica".
DOI: 10.1134/1.1806913
Other Link: http://orcid.org/0000-0001-5237-5718
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Isovector and isoscalar spin-flip M1 strengths in B-11
T Kawabata, H Akimune, H Fujimura, H Fujita, Y Fujita, M Fujiwara, K Hara, KY Hara, K Hatanaka, T Ishikawa, M Itoh, J Kamiya, S Kishi, M Nakmura, K Nakanishi, T Noro, H Sakaguchi, Y Shimbara, H Takeda, A Tamii, S Terashima, H Toyokawa, M Uchida, H Ueno, T Wakasa, Y Yasuda, HP Yoshida, M Yosoi
PHYSICAL REVIEW C 70 ( 3 ) 34318 - 03431810 2004.9
Joint Work
Publisher:AMERICAN PHYSICAL SOC
The B-11(He-3,t), and B-11(d,d(')), and B-11(p,p(')) reactions were measured at forward scattering angles including 0degrees to study the isovector and isoscalar spin-flip M1 strengths in B-11. The measured B-11(He-3,t) cross sections were compared with the results of the distorted-wave impulse-approximation (DWIA) calculation, and the Gamow-Teller (GT) strengths for low-lying states in C-11 were determined. The GT strengths were converted to the isovector spin-flip M1 strengths using the isobaric analog relations under the assumption of the isospin symmetry. The isoscalar spin-flip M1 strengths were obtained from the (d,d(')) analysis by assuming that the shape of the collective transition form factor with the same DeltaJ(pi) is similar in the B-11(d,d(')) and C-12(d,d(')) reactions. The obtained isovector and isoscalar strengths were used in the DWIA calculations for the B-11(p,p(')) reaction. The DWIA calculation reasonably well explains the present B-11(p,p(')) result. However, the calculated cross section for the 8.92-MeV 3/2(2)(-) state was significantly smaller than the experimental values. The transition strengths obtained in the shell-model calculations were found to be 20-50 % larger than the experimental strengths. The transition strengths for the neutrino induced reactions were estimated by using the isovector and isoscalar spin-flip M1 strengths. The present results are quantitatively in agreement with the theoretical estimation discussing the axial isoscalar coupling in the neutrino scattering process, and are useful in the measurement of the stellar neutrinos using the neutral- and charged-current reactions on B-11.
DOI: 10.1103/PhysRevC.70.034318
Other Link: http://orcid.org/0000-0001-5237-5718
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Cluster fragmentations of deep(1s)-hole states in light nuclei
M. Yosoi, H. Akimune, I. Daito, H. Ejiri, H. Fujimura, M. Fujiwara, K. Fushimi, K. Hara, K. Y. Hara, H. Hashimoto, T. Ishikawa, M. Itoh, Y. Itow, S. Kishi, T. Kawabata, K. Kawase, M. Kinoshita, K. Kobayashi, M. Nakamura, K. Nakanishi, Y. Nakatsugawa, S. Nakayama, T. Noro, E. Obayashi, S. Okumura, H. Sakaguchi, Y. Sakemi, M. Shiozawa, H. Takeda, T. Taki, A. Tamii, M. Tanaka, S. Terashima, H. Toyokawa, N. Tsukahara, M. Uchida, T. Yamada, T. Yamagata, Y. Yasuda, H. P. Yoshida, R. G.T. Zegers, J. Zenihiro
Nuclear Physics A 738 ( 1-4 SUPPL. ) 451 - 454 2004.6
Joint Work
Decay particles from the s-hole states in 11B, 15N and 6He have been measured in coincidence with the quasifree 12C(p, 2p), 16O(p, 2p) and 7Li(p, 2p) reactions at 392 MeV incident energy. Triton-decay is found to be larger than α-decay for both s-hole states in 11B and 15N despite its smaller Q-value than that, of α-decay. This supports the selection rule predicted by the microscopic SU(3 -model calculations. The relation between the 6He(s-hole) state and the di-triton cluster structure recently found from the charge exchange reaction is briefly discussed. © 2004 Published by Elsevier B.V.
DOI: 10.1016/j.nuclphysa.2004.04.084
Other Link: http://orcid.org/0000-0001-5237-5718
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Giant dipole resonances and the analogs of α-clusters in A=6 and 7 nuclei
T. Yamagata, S. Nakayama, H. Akimune, M. Fujiwara, K. Fushimi, M. B. Greenfield, K. Hara, K. Y. Hara, K. Hashimoto, K. Ichihara, K. Kawase, M. Kinoshita, Y. Matsui, K. Nakanishi, M. Tanaka, H. Utsonomiya, M. Yosoi
Nuclear Physics A 738 ( 1-4 SUPPL. ) 467 - 470 2004.6
Joint Work
The isovector giant dipole resonance (GDR) of an α-cluster in 6Li and 7Li and the analogs in 6,7He and 6,7Be were searched for by using the 6,7Li(p,p′), 6,7Li(3He,t) and 6,7Li(7Li,7Be) reactions at the incident energies of 300, 450 and 455 MeV, respectively. New dipole resonances were found at Ex=27.0±1.5 MeV in 6Li and at Ex=29.0±1.5 MeV in 7Li, both with widths (FWHM) of 12±2 MeV. In 6He, 6Be, 7He, and 7Be, the dipole resonances with widths of 12±2 MeV were observed at Ex=24.0±1.5, 23.5±1.5, 18.0±1.5, and 28.0±1.5 MeV, respectively. Based on the observed excitation energies, widths and cross sections we conclude that the resonances observed in 67Li are the GDR of the α-cluster and the resonances in 6,7He and 6,7Be are the analogs. The Q-value for the excitation of the GDR in the α-cluster in A=7 nuclei is deeper by 1.6±0.3 MeV than that in A=6. © 2004 Elsevier B.V. All right reserved.
DOI: 10.1016/j.nuclphysa.2004.04.088
Other Link: http://orcid.org/0000-0001-5237-5718
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Tri-nucleon cluster structure in A=6 nuclei above cluster decay threshold
H Akimune, T Yamagata, S Nakayama, M Fujiwara, K Fushimi, K Hara, KY Hara, K Ichihara, K Kawase, Y Matsui, K Nakanishi, A Shiokawa, M Tanaka, H Utsunomiya, M Yosoi
NUCLEAR PHYSICS A 738 ( 1-4 SUPPL. ) 52 - 58 2004.6
Joint Work
Publisher:ELSEVIER SCIENCE BV
Tri-nucleon molecular structures in He-6 and Be-6 were investigated by using the Li-6 ((LiBe)-Li-7-Be-7)He-6 reaction at 455 MeV and Li-6(He-3,t)Be-6 reaction at 450 MeV, respectively. Binary decay into t+t from a broad state at E-x = 18.0 +/- 11.0 MeV in He-6 and into He-3+He-3 from one at E-x = 18.0 +/- 1.2 MeV in Be-6, were observed by measuring tri-nucleon cluster-decays in coincidence with reaction-particles. The branching ratios for binary decay were estimated to be about 0.7 for both He-6 and Be-6. From the angular correlations of decay particles, these states are assigned to be P states.
DOI: 10.1016/j.nuclphysa.2004.04.011
Other Link: http://orcid.org/0000-0001-5237-5718
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Study of the cluster state at E-x=10.3 MeV in C-12
M Itoh, H Akimune, M Fujiwara, U Garg, H Hashimooto, T Kawabata, K Kawase, S Kishi, T Murakami, K Nakanishi, Y Nakatsugawa, BK Nayak, S Okumura, H Sakaguchi, H Takeda, S Terashima, M Uchida, Y Yasuda, M Yosoi, J Zenihiro
NUCLEAR PHYSICS A 738 ( 1-4 SUPPL. ) 268 - 272 2004.6
Joint Work
Publisher:ELSEVIER SCIENCE BV
Inelastic scattering from C-12 have been measured using 386 MeV alpha particles to study the alpha-cluster state at E(x)similar to10 MeV. The broad level at E-x=10.3 MeV was assigned to be 0(+). In the alpha-cluster model, the existence of the 2(+) state was predicted in the same energy region. We have analyzed the (alpha,alpha') cross-section data using the multipole decomposition analysis technique and found the 2(+) component submerged in the broad 0(+) state.
DOI: 10.1016/j.nuclphysa.2004.04.044
Other Link: http://orcid.org/0000-0001-5237-5718
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Photonuclear reaction studies at synchrotron radiation facilities in Japan
H Utsunomiya, KY Hara, S Goko, H Akimune, T Yamagata, M Ohta, H Ohgaki, H Toyokawa, T Hayakawa, T Shizuma, P Mohr, YW Lui, H Ohkuma, H Yonehara, K Soutome, M Arnould
NUCLEAR PHYSICS A 738 ( 1-4 SUPPL. ) 136 - 142 2004.6
Joint Work
Publisher:ELSEVIER SCIENCE BV
New gamma-ray beams at synchrotron radiation facilities will give us unprecedented opportunities to study photonuclear reactions of astrophysical interest. Konan University and the Universite Libre de Bruxelles launch a 5-year project, starting in 2004, of constructing an extended NACRE compilation in which photonuclear reactions obtained within a dedicated international effort will be included.
DOI: 10.1016/j.nuclphysa.2004.04.022
Other Link: http://orcid.org/0000-0001-5237-5718
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H Fujimura, H Akimune, Daito, I, M Fujiwara, K Hara, KY Hara, MN Harakeh, F Ihara, T Inomata, K Ishibashi, T Ishikawa, T Kawabata, A Tamii, M Tanaka, H Toyokawa, T Yamanaka, M Yosoi
PHYSICAL REVIEW C 69 ( 6 ) 64327 2004.6
Joint Work
Publisher:AMER PHYSICAL SOC
Spin-isospin excitations in N-13 have been studied by means of the (He-3,t) and (He-3,tp) reactions at a bombarding energy of E(He-3)=450 MeV. The zero-degree (He-3,t) spectrum is found to be similar to those from the (p,n) reactions at intermediate energies, suggesting a simple direct reaction mechanism at E(He-3)=450 MeV. The Gamow-Teller (GT) states with J(pi)=1/2(-) and 3/2(-) have been strongly excited at theta(lab)=0degrees. The angular distribution of cross sections for the C-13(He-3,t)N-13 reaction and the elastic He-3 scattering off C-13 were obtained at theta(lab)=0degrees-17degrees and at theta(lab)=2degrees-22degrees, respectively. The obtained experimental results were compared with calculations performed in distorted-wave Born approximation. Microscopic structures of the states in N-13 have further been studied by observing decay protons in coincidence with high-energy tritons measured at theta(lab)=0degrees. The branching ratios for proton decay from the GT states in N-13 to the final low-lying T=0 states in C-12 were obtained. The wave functions of the excited states in N-13 are discussed on the basis of obtained experimental data and relevant theoretical calculations.
DOI: 10.1103/PhysRevC.69.064327
Other Link: http://orcid.org/0000-0001-5237-5718
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Systematics of the bimodal isoscalar giant dipole resonance
M Uchida, H Sakaguchi, M Itoh, M Yosoi, T Kawabata, Y Yasuda, H Takeda, T Murakami, S Terashima, S Kishi, U Garg, P Boutachkov, M Hedden, B Kharraja, M Koss, BK Nayak, S Zhu, M Fujiwara, H Fujimura, HP Yoshida, K Hara, H Akimune, MN Harakeh
PHYSICAL REVIEW C 69 ( 5 ) 51301 - 1 2004.5
Joint Work
Publisher:AMERICAN PHYSICAL SOC
The systematic behavior of the isoscalar giant dipole resonance (ISGDR) in Zr-90, Sn-116, S-144 m, and Pb-208 is studied with inelastic a scattering at E-alpha=386 MeV. Multipole-decomposition analysis is applied to extract the excitation strengths of giant resonances from the (alpha, alpha') differential cross sections at theta(lab)= 0.64degrees-13.5degrees. The bimodal structure of the ISGDR is discussed and compared with recent theoretical results from Hartree-Fock + random-phase-approximation calculations.
DOI: 10.1103/PhysRevC.69.051301
Other Link: http://orcid.org/0000-0001-5237-5718