Appearance of light clusters in post-bounce evolution of core-collapse supernovae

We explore the abundance of light clusters in core-collapse supernovae at post-bounce stage in a quantum statistical approach. Adopting the profile of a supernova core from detailed numerical simulations, we study the distribution of light bound clusters up to α particles ($2⩽A⩽4$) as well as heavy nuclei ($A>4$) in dense matter at finite temperature. Within the frame of a cluster-mean-field approach, the abundances of light clusters are evaluated accounting for self-energy, Pauli blocking, and effects of continuum correlations. We find that deuterons and tritons, in addition to ${}^3\mathrm{He}$ and ${}^4\mathrm{He}$, appear abundantly in a wide region from the surface of the proto-neutron star to the position of the shock wave. The appearance of light clusters may modify the neutrino emission in the cooling region and the neutrino absorption in the heating region and, thereby, influence the supernova mechanism.

Figure 1

Density (a), electron fraction (b) and temperature (c) profile of the supernova core at 150 ms after core bounce as a function of the radius. The position of shock wave and the boundaries of heating and cooling regions are indicated in the top and bottom panels.

Figure 2

Mass fraction $X_i$ of light clusters as a function of the radius for the post-bounce supernova core shown in Fig. 1.