28 August 2023 to 1 September 2023
NAOJ (National Astronomical Observatory of Japan)
Asia/Tokyo timezone

Direct measurement of the ${}^{26}$Si($\alpha$, p)${}^{29}$P reaction for the nucleosynthesis in the X-ray bursts

31 Aug 2023, 14:05
5m
Large Seminar Room (Subaru Building) (NAOJ (National Astronomical Observatory of Japan))

Large Seminar Room (Subaru Building)

NAOJ (National Astronomical Observatory of Japan)

Mitaka, Tokyo, Japan

Speaker

Kodai Okawa

Description

In the X-ray bursts, the $\alpha$p-process, that consists of alternating ($\alpha$, p) and (p, $\gamma$) reactions, is considered to have a great impact on the light curve. However, most of the important reactions have not been understood experimentally because of technical difficulties. The ${}^{26}$Si($\alpha$, p)${}^{29}$P reaction rate is one of the $\alpha$p-process reactions and it is considered that the reaction rate has high sensitivity to the X-ray burst light curve. Therefore, a direct measurement of the reaction was performed at the CNS RI beam separator (CRIB). CRIB produced a ${}^{26}$Si beam with a typical intensity of $3.2 \times 10^4$ pps and a purity of 29%, which bombarded the ${}^{4}$He gas target. We measured the reaction particles using five telescopes consisting of three and four silicon detectors. The ${}^{26}$Si($\alpha$, p)${}^{29}$P reaction was measured up to the center-of-mass energy of about 7.5 MeV, corresponding to about 3 GK of Gamow energy, using the thick gas target method. Because of insufficient statistics, the statistical error became large but an upper limit on the cross section was obtained, which was 0.134 times that of the NON-SMOKER statistical model. The results are useful for comparing experimental and theoretical values at higher temperatures and for constraining the ${}^{26}$Si($\alpha$, p)${}^{29}$P reaction rate.
The analysis method and the results will be discussed.

Primary authors

Kodai Okawa Minju Kim (Department of Physics, Sungkyunkwan University) Kyungyuk Chae (Department of Physics, Sungkyunkwan University) Seiya Hayakawa (Center for Nuclear Study, the University of Tokyo) Satoshi Adachi (Department of Physics, Osaka University) Soomi Cha (Center for Exotic Nuclear Studies, Institute for Basic Science (IBS) ) Thomas William Chillery (Center for Nuclear Study, the University of Tokyo) Tatsuya Furuno (Department of Physics, Osaka University) Gyungmo Gu (Department of Physics, Sungkyunkwan University) Shutaro Hanai (Center for Nuclear Study, the University of Tokyo) Nobuaki Imai (Center for Nuclear Study, the University of Tokyo) David Kahl (Extreme Light Infrastructure Nuclear Physics (ELI-NP) ) Takahiro Kawabata (Department of Physics, Osaka University) Chanhee Kim (Department of Physics, Sungkyunkwan University) Dahee Kim (Center for Exotic Nuclear Studies, Institute for Basic Science (IBS) ) Sohyun Kim (Department of Physics, Sungkyunkwan University) Shigeru Kubono (RIKEN Nishina Center) Minsik Kwag (Department of Physics, Sungkyunkwan University) Jiatai Li (Center for Nuclear Study, the University of Tokyo) Nanru Ma (Center for Nuclear Study, the University of Tokyo) Shin’ichiro Michimasa (Center for Nuclear Study, the University of Tokyo) Uyen Nguyen Kim (Department of Physics, Sungkyunkwan University) Duy Nguyen Ngoc (Department of Physics, Sungkyunkwan University) Kohsuke Sakanashi (Department of Physics, Osaka University) Hideki Shimizu (Center for Nuclear Study, the University of Tokyo) Oana Sirbu (Extreme Light Infrastructure Nuclear Physics (ELI-NP) ) Hidetoshi Yamaguchi (Center for Nuclear Study, the University of Tokyo) Rin Yokoyama (Center for Nuclear Study, the University of Tokyo) Qian Zhang (Center for Nuclear Study, the University of Tokyo)

Presentation materials