BARONET: A (Practical?) Nuclear Network Geared Towards Coupling with Hydrodynamics Simulations

by Dr Federico Guercilena (University of Trento)

Friday 27 Sept 2024, 14:00 → 15:00 Europe/Berlin

SR102 (Abbeanum)

Accounting for out-of-NSE (nuclear statistical equilibrium) r-process nucleosynthesis is one of the most sought-after goals in the (numerical) modelling of binary neutron star (BNS) mergers. While post-processing analysis via full nuclear networks is a reliable technique, the computational and storage costs prevent such calculations to be directly coupled to hydrodynamics codes, thus neglecting the dynamical influence of the r-process heating. We present here a novel framework, akin to a reduced network, based on top of the "beta-flow" approximation, that drastically reduces the computational and storage requirements w.r.t. a full network while returning accurate predictions for both isotope abundances and heating rate. This technique features: 1) far less degrees of freedom than a full network (~500
 vs. ~7500); 2) explicit split between dominant/subdominant and fast/slow reactions; 3) ability to accurately track the time evolution of abundances and heating rate. We summarize its base assumptions and derivation and practical implementation issues.