Speaker
Description
$\alpha$-induced reactions play an essential role in various astrophysical scenarios. For intermediate mass and heavy target nuclei, various $\alpha$-nucleus optical model potentials (AOMP) predict reaction rates which may differ by orders of magnitude. This wide range of predictions complicates nucleosynthesis calculations in reaction networks, in particular for the $p$-process with uncertain ($\gamma$,$\alpha$) rates and for the weak $r$-process with uncertain ($\alpha$,$x n$) rates.
The reason for this wide range of predictions is mainly the tail of the imaginary part of the AOMP (as identified in [1]). The new Atomki-V2 potential was suggested to overcome this problem, and it was found that predictions of the Atomki-V2 potential match the available experimental data with deviations of less than a factor of two in all cases [1]. Reaction rates from the Atomki-V2 potential have been calculated for 4359 nuclei between iron ($Z = 26$) and bismuth ($Z = 83$) [2].
This talk will present:
($i$) the derivation of the Atomki-V2 AOMP [1,2] and a comparison to other global AOMPs;
($ii$) the verification of the Atomki-V2 AOMP using latest data for the $^{96}$Zr($\alpha$,$n$)$^{99}$Mo and $^{100}$Mo($\alpha$,$n$)$^{103}$Ru reactions which are relevant of the weak $r$-process [3,4];
($iii$) the impact of the reaction rates from the Atomki-V2 AOMP and its reduced uncertainties on the weak $r$-process [5].
As an outlook, it will become possible in the near future to test the Atomki-V2 predictions of cross sections of $\alpha$-induced reactions for unstable nuclei in several upcoming experiments with radioactive beams.
[1] P. Mohr et al., Phys. Rev. Lett. 124, 252701 (2020).
[2] P. Mohr et al., At. Data Nucl. Data Tables 142, 101453 (2021).
[3] G. G. Kiss et al., Astroph. J. 908, 202 (2021).
[4] T. N. Szegedi et al., Phys. Rev. C 104, 035804 (2021).
[5] A.\ Psaltis et al., Astroph. J., submitted (arXiv:2204.07136).
| Length of presentation requested | Oral presentation: 25 min + 5 min questions (Review-type talk) |
|---|---|
| Please select between one and three keywords related to your abstract | Nuclear physics - theory |
| 2nd keyword (optional) | Nuclear physics - experimental |
| 3rd keyword (optional) | Nucleosynthesis |
