Speaker
Description
This study presents the first direct measurement of the $^{14}\mathrm{O}(α,p)^{17}\mathrm{F}$ cross section using an active target time projection chamber. The reaction is one of the key reactions influencing the light curve of Type I X-ray burst models [1]. Additionally, this reaction rate plays an important role in the break-out from the hot CNO cycle to the rp-process at high temperatures (T$_9$ > 0.5) [2]. However, due to the lack of experimental data, its precise contribution to astrophysical observables has remained uncertain.
To address this challenge, a direct measurement of the $^{14}\mathrm{O}(α,p)^{17}\mathrm{F}$ cross section was performed. A $^{14}$O beam was produced at the CNS Radioactive Ion Beam separator (CRIB) at RIKEN [3], using an 8.40 MeV/u $^{14}$N beam and a H$_2$ cryogenic gas-cell target. The experiment utilized the Texas Active Target Time Projection Chamber (TexAT), which was originally developed at Texas A&M University [4]. The device was upgraded to TexAT_v2 by the Institute for Basic Science (IBS) to allow high beam intensity and low-energy proton detection capability [4, 5]. The three-dimensional tracking capability of TexAT_v2 improves the energy and position resolution of detected particles, enhancing cross-section measurements. The excitation function of the $^{18}$Ne compound nucleus was successfully measured down to about 0.5 MeV in center-of-mass energy.
The experimental setup, as well as analysis results, will be presented and discussed.
References
[1] R. H. Cyburt et al., Astrophys. J. 830, 55 (2016).
[2] R. K. Wallace and S. E. Woosley, Astro. J. Suppl. Ser. 45, 389 (1981).
[3] S. Kubono et al., Eur. Phys. J. A 13, 217 (2002)
[4] E. Koshchiy et al., Nucl. Inst. and Meth. A 957, 163398 (2020).
[5] C. Park et al., Nucl. Inst. and Meth. B 541 (2023)
