Speaker
Description
Type-I X-ray bursts are thermonuclear explosions in the atmospheres of accreting neutron stars in close binary systems. During these bursts, temperatures are achieved ($0.8-1.5\,\mathrm{GK}$) such that breakout from the HCNO cycle occurs, resulting in a whole new set of thermonuclear reactions; the rp-process.
Sensitivity studies have highlighted the ${}^{59}\mathrm{Cu}(p,\gamma){}^{60}\mathrm{Zn}$ reaction as significant in its impact along the rp-process path. In particular, competition between the ${}^{59}\mathrm{Cu}(p,\alpha){}^{56}\mathrm{Ni}$ and ${}^{59}\mathrm{Cu}(p,\gamma){}^{60}\mathrm{Zn}$ reactions within the NiCu cycle determines whether nucleosynthesis flows towards higher-mass regions. At present, stellar reaction rates for both of these processes are based entirely on statistical-model calculations.
Recently, however, an indirect study of the nucleus $^{60}\mathrm{Zn}$ has surprisingly shown a plateau in the level-density of states in the region of interest, contrary to the usual expectation of exponential growth with increasing excitation energy. As a result, a statistical-model approach of the ${}^{59}\mathrm{Cu}(p,\gamma)$ reaction rate may be insufficient, and it is therefore now essential to explore the properties of excited states in $^{60}\mathrm{Zn}$ that influence the astrophysical ${}^{59}\mathrm{Cu}(p,\gamma){}^{60}\mathrm{Zn}$ reaction.
In this work, we aim to utilise the ${}^{59}\mathrm{Cu}(d,n)$ reaction in inverse kinematics at the Facility for Rare Isotope Beams (FRIB) to obtain the first measurement of resonances in the ${}^{59}\mathrm{Cu}(p,\gamma)$ reaction.
