Papers - AKIMUNE Hidetoshi
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Trinucleon cluster structures in Li-6
S Nakayama, T Yamagata, H Akimune, M Fujiwara, K Fushimi, MB Greenfield, K Hara, KY Hara, H Hashimoto, K Ichihara, K Kawase, H Matsui, K Nakanishi, M Sakama, M Tanaka, M Yosoi
PHYSICAL REVIEW C 69 ( 4 ) 41304 - 1 2004.4
Joint Work
Publisher：AMER PHYSICAL SOC
The t+He-3 cluster structures in Li-6 were investigated by using the Li-7(He-3,alpha) reaction at 450 MeV and at theta(L)=0degrees. A binary decay into t+He-3 with a branching ratio of 0.8+/-0.2 from a broad state at E-x=21 MeV in Li-6 was observed by measuring t and He-3 decay particles. From the measured angular correlations and with the analysis of the spectral shape by using the Breit-Wigner formula, the 21-MeV resonance was decomposed into the P-1 (T=0) state at E-x=18.0+/-0.5 MeV with Gamma(FWHM)=5.0+/-0.5 MeV (where FWHM means full width at half maximum), and the P-3 (T=1) state at E-x=22+/-1 MeV with Gamma=8+/-1 MeV.
DOI： 10.1103/PhysRevC.69.041304
Other Link： http://orcid.org/0000-0001-5237-5718
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Excitations of the alpha cluster in A=6 and 7 nuclei
T Yamagata, S Nakayama, H Akimune, M Fujiwara, K Fushimi, MB Greenfield, K Hara, KY Hara, H Hashimoto, K Ichihara, K Kawase, M Kinoshita, Y Matsui, K Nakanishi, M Tanaka, H Utsunomiya, M Yosoi
PHYSICAL REVIEW C 69 ( 4 ) 44313 - 1 2004.4
Joint Work
Publisher：AMERICAN PHYSICAL SOC
The isovector giant dipole resonance (GDR) of an alpha cluster in Li-6 and Li-7, and its analogs in Be-6,Be-7 and He-6,He-7 were searched for by using the Li-6,Li-7(p,p(')), Li-6,Li-7(He-3,t), and Li-6,Li-7(Li-7,Be-7) reactions at the incident energies of 300, 450, and 455 MeV, respectively. New dipole resonances were found at E-x=27.0+/-1.5 MeV in Li-6 and at E-x=29.0+/-1.5 MeV in Li-7, both with widths (full width at half maximum) of 12+/-2 MeV. In He-6, Be-6, He-7, and Be-7, the dipole resonances with a width of 12+/-2 MeV were observed at E-x=24.0+/-1.5,23.5+/-1.5,18.0+/-1.5, and 28.0+/-1.5 MeV, respectively. The resonance shapes were reproduced well with the GDR shape observed in the He-4(gamma,n) reactions. The averaged value for the ratios of the resonance cross section in A=6 to that in A=7 for each element was 1.2+/-0.3. The averaged value for the ratios of the resonance cross section to the GDR cross section in the respective target nuclei was 0.44+/-0.08, which was consistent with the ratios of the GDR cross section in He-4 to that in Li-6,Li-7 reported in the photonuclear reactions. The excitation energies for the dipole resonances in A=6 and 7 nuclei relative to the separation energies of an alpha particle in Li-6 and Li-7, respectively, agreed well with the excitation energy for the GDR in He-4 (similar to26 MeV). We conclude that the resonances observed in Li-6,Li-7 are consistent with the GDR of the alpha cluster and the resonances in He-6,He-7 and Be-6,Be-7 are consistent with the analogs of the GDR in the alpha cluster. The Q value for the excitation of the GDR of the alpha cluster in A=7 nuclei is deeper by 1.6+/-0.3 MeV on the average than that in A=6.
DOI： 10.1103/PhysRevC.69.044313
Other Link： http://orcid.org/0000-0001-5237-5718
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The effect of deformation in the isoscalar giant dipole resonance
M Itoh, H Sakaguchi, M Uchida, T Ishikawa, T Kawabata, T Murakami, H Takeda, T Taki, S Terashima, N Tsukahara, Y Yasuda, M Yosoi, U Garg, M Hedden, B Kharraja, M Koss, BK Nayak, S Zhu, H Fujimura, M Fujiwara, K Hara, HP Yoshida, H Akimune, MN Harakeh, M Volkerts
NUCLEAR PHYSICS A 731 ( 1-4 ) 41 - 48 2004.2
Joint Work
Publisher：ELSEVIER SCIENCE BV
Background-free inelastic scattering spectra have been obtained for <SUP>144,148,150,152,154</SUP>Sm with 386 MeV alpha particles at forward angles (including 0degrees) to investigate the effect of deformation on the isoscalar giant dipole resonance. The strength distributions for isoscalar giant resonances have been extracted via a multipole decomposition analysis using angular distributions calculated in the framework of the density-dependent single-folding model. The effects of deformation are found to be different for the low- and high-excitation energy components of the isoscalar giant dipole resonance. Evidence has been obtained for the theoretically-predicted mixing between the isoscalar giant dipole resonance and the high energy octupole resonance.
DOI： 10.1016/j.nuclphysa.2003.11.017
Other Link： http://orcid.org/0000-0001-5237-5718
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t+He-3 molecular structures in Li-6 studied by (He-3,alpha) reaction at 450 MeV
S Nakayama, T Yamagata, H Akimune, M Fujiwara, K Fushimi, MB Greenfield, K Hara, KY Hara, K Hashimoto, K Ichihara, K Kawase, Y Matsui, K Nakanishi, M Sakama, M Tanaka, M Yosoi
NUCLEAR PHYSICS A 731 ( 1-4 ) 355 - 362 2004.2
Joint Work
Publisher：ELSEVIER SCIENCE BV
Tri-nucleon cluster-structures in Li-6 were investigated by using the Li-7 (He-3,alpha) reaction at 450 MeV and at theta(L) = 0degrees. A binary decay into t+ He-3 from a broad peak at E-x = 21 MeV was observed. The branching ratio for the binary decay was estimated to be 0.8 +/- 0.2. From the measured angular correlations and the analysis of the spectral shape by using the Breit-Wigner formula, the peak was identified to be composed of two tri-nucleon cluster-states (t + He-3) of the P-1-state at E-x = 18 MeV with a width (FWHM) of 5 MeV and the P-3-state at E-x = 22 MeV with a width of 8 MeV.
DOI： 10.1016/j.nuclphysa.2003.11.048
Other Link： http://orcid.org/0000-0001-5237-5718
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Neutron-skin thickness in neutron-rich isotopes
A Krasznahorkay, H Akimune, AM van den Berg, N Blasi, S Brandenburg, M Csatlos, M Fujiwara, J Gulyas, MN Harakeh, M Hunyadi, M de Huu, Z Mate, D Sohler, SY van der Werf, HJ Wortche, L Zolnai
NUCLEAR PHYSICS A 731 ( 1-4 ) 224 - 234 2004.2
Joint Work
Publisher：ELSEVIER SCIENCE BV
After a short overview of the methods applied for measuring the neutron-skin thickness, we present the recent experimental results for the neutron-skin thicknesses of the Sn112-124 even-even isotopes and of Pb-208. We have used inelastic alpha scattering to excite the giant dipole resonance (GDR). The cross section of this process depends strongly on DeltaR(np)/R, the relative neutron-skin thickness. We have also measured the excitation of the spin-dipole resonance (SDR) to deduce the neutron-skin thickness since the summed L=1 strength of the SDR is sensitive to it. The results obtained are in good agreement with the previous experimental and theoretical ones.
DOI： 10.1016/j.nuclphysa.2003.11.034
Other Link： http://orcid.org/0000-0001-5237-5718
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RGT Zegers, H Abend, H Akimune, AM van den Berg, H Fujimura, H Fujita, Y Fujita, M Fujiwara, S Gales, K Hara, MN Harakeh, T Ishikawa, T Kawabata, K Kawase, T Mibe, K Nakanishi, S Nakayama, H Toyokawa, M Uchida, T Yamagata, K Yamasaki, M Yosoi
NUCLEAR PHYSICS A 731 ( 1-4 ) 121 - 128 2004.2
Joint Work
Publisher：ELSEVIER SCIENCE BV
The excitation and subsequent decay by proton emission of the isovector spin-flip giant monopole resonance are studied via the Pb-208 (He-3, t) reaction at 410 MeV. In the tritonsingles spectrum 60 +/- 5% of the non-energy-weighted sum-rule strength for this 2hw resonance is found in the region 29 < E-x (Bi-208) < 51 MeV. The central excitation energy and width of the IVSGMR are determined to be 37 +/- 1 MeV and 14 +/- 3 MeV, respectively.
DOI： 10.1016/j.nuclphysa.2003.11.024
Other Link： http://orcid.org/0000-0001-5237-5718
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Tri-nucleon cluster structure in 6He and 6Be
Akimune H, Yamagata T, Nakayama S, Fujiwara M, Fushimi K, Hara K, Hara K.Y, Ichihara K, Kawase K, Matsui K, Nakanishi K, Shiokawa A, Tanaka M, Utsunomiya H, Yosoi M
AIP Conference Proceedings 704 253 - 260 2004
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Search for excited α-cluster resonances and their analogs in A=6 and 7 nuclei
Yamagata T, Nakayama S, Akimune H, Fujiwara M, Fushimi K, Greenfield M.B, Hara K, Hara K.Y, Hashimoto K, Ichihara K, Kawase K, Kinoshita M, Matsui Y, Nakanishi K, Tanaka M, Utsunomiya H, Yosoi M
AIP Conference Proceedings 704 261 - 272 2004
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H Ohkuma, Y Arimoto, K Kawase, K Tamura, S Suzuki, T Yorita, M Shoji, K Nakanishi, H Akimune, M Fujiwara, S Okajima
CONFERENCE DIGEST OF THE 2004 JOINT 29TH INTERNATIONAL CONFERENCE ON INFRARED AND MILLIMETER WAVES AND 12TH INTERNATIONAL CONFERENCE ON TERAHERTZ ELECTRONICS 789 - 790 2004
Joint Work
Publisher：IEEE
For MeV gamma-ray production by the backward Compton scattering (BCS), a high power optically-pumped far infrared (FIR) laser has been developed at the synchrotron radiation facility of SPring-8. We obtained about 1.6-W of output power of FIR laser at CH3OH 119-mum lasing line pumped by 9P(36) branch line of CO2 laser. We have constructed a test beamline for a production of 10-MeV gamma-ray using an accelerator beam diagnosis beamline. FIR laser photons are injected to the beamline against 8-GeV stored electron beam and produced MeV gamma-rays are extracted to the beamline. We proceed with a gamma-ray production test now at this beamline. It is estimated that the MeV gamma-rays of 103 photons/sec are obtained with FIR output power of 1.6 W at the test beamline. In future plan, the intensity of gamma-ray will reach to 10(7) phtons/sec or more by means of installation of an intense MeV gamma-ray production system by BCS at an another new beamline.
Other Link： http://orcid.org/0000-0001-5237-5718
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Photodisintegration of Deuterium in the Precision Era of Big Bang Nucleosynthesis
Hara K.Y, Utsunomiya H, Akimune H, Goko S, Kudo K, Lui Y.-W, Ohgaki H, Ohta M, Shibata Y, Toyokawa H, Uritani A, Yamagata T
AIP Conference Proceedings 704 551 - 556 2004
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Photoreaction Cross Section Measurements for Astrophysics
Utsunomiya H, Goko S, Hara K.Y, Akimune H, Yamagata T, Ohta M, Ohgaki H, Toyokawa H, Hayakawa T, Shizuma T, Lui Y.-W, Mohr P
AIP Conference Proceedings 704 439 - 446 2004
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Kawabata T, Akimune H, Fujimura H, Fujita H, Fujita Y, Fujiwara M, Hara K, Hara K.Y, Hatanaka K, Ishikawa T, Itoh M, Kamiya J, Nakamura M, Sakaguchi H, Shimbara Y, Takeda H, Tamii A, Noro T, Toyokawa H, Uchida M, Wakasa T, Yasuda Y, Yoshida H.P, Yosoi M
Physics of Atomic Nuclei 67 ( 10 ) 1974 - 1798 2004
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Systematic study of L <= 3 giant resonances in Sm isotopes via multipole decomposition analysis
M Itoh, H Sakaguchi, M Uchida, T Ishikawa, T Kawabata, T Murakami, H Takeda, T Taki, S Terashima, N Tsukahara, Y Yasuda, A Yosoi, U Garg, M Hedden, B Kharraja, M Koss, BK Nayak, S Zhu, H Fujimura, M Fujiwara, K Hara, HP Yoshida, H Akimune, MN Harakeh, A Volkerts
PHYSICAL REVIEW C 68 ( 6 ) 64602 2003.12
Joint Work
Publisher：AMER PHYSICAL SOC
Background-free inelastic scattering spectra have been obtained for five Sm isotopes with 386-MeV a particles at forward angles (including 0degrees) to investigate the effect of deformation on the compressional-mode giant resonances. The strength distributions for the Lless than or equal to3 isoscalar giant resonances have been extracted via a multipole decomposition analysis using angular distributions calculated in the framework of the density-dependent single-folding model. We observed a splitting of the giant monopole resonance because of its mixing with the giant quadrupole resonance. For the isoscalar giant dipole resonance, the observed effects of deformation are different for the low- and high-excitation-energy components. Evidence has been obtained for the theoretically predicted mixing between the isoscalar giant dipole resonance and the high energy octupole resonance.
DOI： 10.1103/PhysRevC.68.064602
Other Link： http://orcid.org/0000-0001-5237-5718
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Microscopic structure of the Gamow-Teller resonance in 58Cu Reviewed
K. Hara, T. Adachi, H. Akimune, I. Daito, H. Fujimura, Y. Fujita, M. Fujiwara, K. Fushimi, K. Y. Hara, M. N. Harakeh, K. Ichihara, T. Ishikawa, J. Jänecke, J. Kamiya, T. Kawabata, K. Kawase, K. Nakanishi, Y. Sakemi, Y. Shimbara, Y. Shimizu, M. Uchida, H. P. Yoshida, M. Yosoi, R. G.T. Zegers
Physical Review C - Nuclear Physics 68 ( 6 ) 646121 - 646129 2003.12
Joint Work
The Gamow-Teller (GT) states in 58Cu have been studied via the 58Ni(3He, t+p) and 58Ni(3He, t+γ) coincidence experiments. The GT states in 58Cu at E X=6-12 MeV, where both T=1 and 1=2, 1+ states exist, are excited strongly in the 58Ni(3He, f) reaction at E( 3He)=450 MeV and θ=0°. Proton emissions from the GT states in 58Cu to the hole states in 57Ni have been observed with solid-state detectors in coincidence with high energy tritons measured with a magnetic spectrometer. For the first time, the γ-ray emissions from the excited states in 58Cu and in 37Ni, following the 58Ni(3He, t+p) reaction at intermediate energies, have also been observed in coincidence with tritons. Strengths of proton decay into several neutron-hole states in 57Ni and γ-decay strengths are used to discuss the wave functions of the GT states in 58Cu. The T= 1 and T=2 GT states do only weakly decay into a T=3/2, f7/2-1 neutron-hole state at 5.230 MeV in 57Ni, which is strongly excited via the 58Ni(p, d)57Ni reaction. The wave functions of the T=1 and T=2 GT states with the f7/2-1 neutron-hole configuration are inferred to be strongly coupled to 2p-2h configurations, making fragmented GT strengths in 58Cu.
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Structure and decay of the s-hole state in 11B studied via the 12C(p,2p)11B* reaction
秋宗 秀俊
Phys. Lett. 551B 255 2003.11
Single Work
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Isoscalar giant dipole resonance in 208Pb via inelastic scattering at 400 MeV and nuclear incompressibility
秋宗 秀俊
Phys. Lett. B 557 12-19 2003.11
Single Work
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Excitation and Decay of the Isovector Giant Monopole Resonances
秋宗 秀俊
Phys. Rev. Lett. 90, 202501 2003.11
Single Work
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Evidence for a Narrow S=+1 Baryon Resonance in Photoproduction from the Neutron
秋宗 秀俊
Phys. Rev. Lett. 91, 012002 2003.11
Single Work
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Beam-Polarization Asymmetries for the p(gamma_pol,K+)Lambda and p(gamma_pol,K+)Ksi0 Reactions for E_gamma = 1.5?2.4 GeV
秋宗 秀俊
Phys. Rev. Lett. 91, 092001 2003.11
Single Work
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Di-triton molecular structure in 6He
秋宗 秀俊
Phys. Rev. C 67, 051302R 2003.11
Single Work