- snd2019@cabas.kyushu-u.ac.jp
Contact 連絡先
Contribution Poster
Study of an angular correlation of $\gamma$-rays emitted by 117Sn(n,$\gamma$) reactions for T-violation search
Speakers
- Mr. Jun KOGA
Primary authors
- Mr. Jun KOGA (Kyushu University)
Co-authors
- Mr. Shunsuke ENDO (Japan Atomic Energy Agency)
- Dr. Hiroyuki FUJIOKA (Tokyo Institute of TEchnology)
- Dr. Katsuya HIROTA (Nagoya University)
- Mr. Kohei ISHIZAKI (Nagoya University)
- Dr. Atsushi KIMURA (Japan Atomic Energy Agency)
- Dr. Masaaki KITAGUCHI (Nagoya University)
- Mr. SO MAKISE (Department of Physics, Graduate School of Science, Kyushu University,)
- Mr. Yudai NIINOMI (Nagoya University)
- Dr. Takuya OKUDAIRA (Japan Atomic Energy Agency)
- Dr. Kenji SAKAI (Japan Atomic Energy Agency)
- Dr. Tatsushi SHIMA (Osaka University)
- Prof. Hirohiko SHIMIZU (Nagoya University)
- Mr. Shusuke TAKADA (Kyushu University)
- Ms. Yuika TANI (Tokyo Institute of Technology)
- Mr. Tomoki YAMAMOTO (Nagoya University)
- Mr. Hiromoto YOSHIKAWA (Osaka University)
- Dr. Tamaki YOSHIOKA (Kyushu University)
日本語タイトル
時間反転対称性の破れ探索に向けた117Sn(n,γ)反応によるγ線角相関に関する研究
Abstract
The breaking of parity symmetry and charge conjugation (CP-violation) is necessary to explain a difference between the number of matter and that of antimatter in the current universe. Assuming the CPT theorem, CP-violation means the violation of time reversal invariance. It is theoretically suggested that T-violation could be enhanced in compound nuclear reactions by an interference between an amplitude of a s-wave resonance and that of a p-wave resonance. This theory predicts that one of key parameters for T-violation search is a spin factor $\kappa$(J) which corresponds to experimental sensitivity. The value of $\kappa$(J) depends on nuclear species and can be determined by measuring an angular correlation of $\gamma$-rays produced by (n,$\gamma$) reactions which compound nuclear state in a p-wave resonance decays to a specific state. If a nucleus has large $\kappa$(J), it becomes a candidate for T-violation search. To determine the value of $\kappa$(J) of 117Sn, which is easy to measure angular correlation because its p-wave resonance ca be clearly observed, we measured the angular correlation of $\gamma$-rays emitted from the compound states at J-PARC MLF BL04. The angular correlation was observed clearly when the compound state decays to a ground state. In addition, we conducted an experiment for determining a branching ratio which the compound state decays to the ground state in the (n,$\gamma$) reaction. In this poster, we will report the experimental result and analysis status.