Effects of the temperature dependence of the in-medium nucleon mass on core-collapse supernovae

Abstract

Aims. A complete description of the core collapse supernova mechanism requires an appropriate treatment of both the hydrodynamics and the microphysics. We study the influence of a nuclear physics input, namely the temperature dependence of the nucleon effective mass in nuclei induced by the in-medium effects, in the core collapse of a massive star. Methods. We present here the first implementation of this nuclear input in a hydrodynamical one-dimensional simulation. The simulations are performed with a spherically symmetric Newtonian model, with neutrino transport treated in the multi-group flux-limited diffusion approximation. Results. The inclusion of the temperature dependence of the in-medium nucleon mass has an impact on the equation of state of the system and reduces the deleptonisation during the collapse. This results in a non-negligible effect on the shock wave energetics. The shock wave is formed more outwards, and in the first few milliseconds after bounce the shock front has propagated further out.

Equations of state for supernovae and compact stars

“…In both cases, the surface and bulk properties of nuclei are modified as compared to the vacuum at zero temperature. One aspect is a temperature dependence of the symmetry energy (Dean, Langanke, and Sampaio, 2002;Agrawal et al, 2014) and of effective nucleon masses (Donati et al, 1994;Fantina et al, 2012). Obviously, such temperature effects are related to excited states and internal partition functions but the problem is approached from a different perspective.…”

“…This is important for detailed predictions of NS radii and for dynamical properties. Only few such unified NS EoSs exist, see, e.g., Douchin and Haensel (2001); Fantina et al (2013); Miyatsu et al (2013); Baldo et al (2014); Gulminelli and Raduta (2015). Unified NS EoSs can also be obtained from the general purpose EoS, which will be discussed in Sec.…”

Extended equation of state for core-collapse simulations

“…Indeed, mean field theories predict an average effective mass m * /m around 0.6-0.8 (see, e.g., Bender et al [27] for a review, and references therein). It has been shown that the inclusion of a temperature-dependent nucleon effective mass in nuclei, coming from dynamical correlations beyond mean field, may affect the core-collapse dynamics [28][29][30]. However, as mentioned earlier the details of the nuclear part are not the aim of the present work, and we keep the original version of Lattimer and Swesty [3].…”

Spin-isospin response in finite nuclei from an extended Skyrme interaction

“…They play, for instance, an important role in predicting β decay halflives of neutron rich nuclei involved in the r-process of the nucleosynthesis [7]. In core-collapse supernova, the GT transitions of pf-shell nuclei give an important contribution to the weak interaction decay rates that play an essential role in the core-collapse dynamics of massive stars [8][9][10]. The neutrino-induced nucleosynthesis may take place via GT processes in neutron-rich environment [11].…”