Measurement of the isomer production ratio for the $$^{112}$$Cd($$n,gamma$$)$$^{113}$$Cd reaction using neutron beams at J-PARC
早川 岳人*; 藤 暢輔; Huang, M.; 静間 俊行*; 木村 敦; 中村 詔司; 原田 秀郎; 岩本 信之; 千葉 敏*; 梶野 敏貴*
Hayakawa, Takehito*; Toh, Yosuke; Huang, M.; Shizuma, Toshiyuki*; Kimura, Atsushi; Nakamura, Shoji; Harada, Hideo; Iwamoto, Nobuyuki; Chiba, Satoshi*; Kajino, Toshitaka*
The astrophysical origin of a rare isotope $$^{115}$$Sn has remained still an open question. An isomer ($$T_{1/2}$$=14.1 y) in $$^{113}$$Cd is an s-process branching point from which a nucleosynthesis flow reaches to $$^{115}$$Sn. The $$s$$-process abundance of $$^{115}$$Sn depends on the isomer production ratio in the $$^{112}$$Cd($$n,gamma$$)$$^{113}$$Cd reaction. However, the ratio has not been measured in an energy region higher than the thermal energy. We have measured $$gamma$$ rays following neutron capture reactions on $$^{112}$$Cd using two cluster HPGe detectors in conjunction with a time-of-flight method at J-PARC. We have obtained the result that the relative $$gamma$$-ray intensity ratio of the isomer is almost constant in an energy region of up to 5 keV. This result suggests that the $$s$$-process contribution to the solar abundance of $$^{115}$$Sn is negligibly small. We have found that the ratio of a resonance at 737 eV shows about 1.5 times higher than other ratios. This enhancement can be explained by a $$p$$-wave neutron capture. This result suggests measurements of decay $$gamma$$ rays to isomers are effective to assign the spin and parity for neutron capture resonances.
使用言語 : English
掲載資料名 : Physical Review C
: 94
: 5
ページ数 : p.055803_1 - 055803_6
発行年月 : 2016/11
出版社名 : American Physical Society
特許データ :
論文URL :
キーワード : J-PARC ANNRI; 即発ガンマ線; 飛行時間法; 天体物理学
使用施設 :
広報プレスリリース :
受委託・共同研究相手機関 :
登録番号 : AA20160294
抄録集掲載番号 : 44001639
論文投稿番号 : 18313
Accesses  (From Jun. 2, 2014)
- Accesses
分野:Physics, Nuclear
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