Speaker
Description
Nucleosynthesis is an ongoing process in the cosmos which take place in various astrophysical environments such as massive stars, core-collapse supernovae or novae. One of the most famous example of evidence in the continuity of the process was the discovery of $\gamma$-ray from radioactive $^{26}$Al in 1982 [1]. More recently, an all-sky map of this characteristic 1809-keV $\gamma$-ray shows a distribution of $^{26}$Al in favor of massive stars and supernovae as the main progenitors [2]. Nevertheless, observational data are not enough to define precisely the source of production of $^{26}$Al and 14 to 29$\%$ of the total observed $^{26}$Al abundance are expected to have a nova origin [3].
In order to have a more precise picture of the different possible scenario, the $^{25}$Al(p, $\gamma$)$^{26}$Si reaction has been studied in nuclear facilities. This reaction has a direct influence on the abundance of $^{26}$Al, by bypassing the $^{25}$Mg(p, $\gamma$)$^{26}$Al reaction responsible of the production of the $^{26}$Al cosmic $\gamma$-ray emitter.
In this contribution, I’ll present results which illustrate two complementary experimental domains: Mass measurement and gamma-ray spectroscopy. In $^{25}$Al(p, $\gamma$)$^{26}$Si reaction, the proton capture is dominated by resonant capture to a few states above the proton threshold in $^{26}$Si. The mass value of $^{25}$Al and $^{26}$Si have an exponential contribution to the total resonant proton capture rate in $^{26}$Si. The mass of $^{25}$Al has been precisely determined via Penning traps measurement in the IGISOL facility at the university of Jyvaskyla in Finland [5]. Additionally, a recent experiment at Argonne National Laboratory in USA was performed to identify the resonant states in $^{26}$Si via $\gamma$-ray spectroscopy study using the unique GRETINA+FMA setup. This experiment came in complement to a recent spectroscopy study of the $^{26}$Si mirror nucleus, $^{26}$Mg, where a previously unaccounted l=1 resonance in the $^{25}$Al +p system was observed [5].
[1] W. A. Mahoney, J. Ling, A. Jacobson, and R. Lingenfelter, Astrophys. J. 262, 742 (1982).
[2] R. Diehl et al., Astron. and Astrophys., 298:445 (1995).
[3] M. B. Bennett et al., Phys. Rev. Lett. 111, 232503 (2013).
[4] L. Canete et al., Eur. Phys. J. A 52, 124 (2016).
[5] L. Canete et al., Phys. Rev. C 104, L022802 (2021).
