Nuclear Physics Seminar with Alex Haber and Lorenzo Andreoli

"Transport in Neutron Star Mergers" presented by Alex Haber  from Washington University in St. Louis

Transport properties of compact stars have been computed in the past mostly for the conditions  in old, isolated and therefore cold neutron stars. Gravitational wave observations of binary neutron star mergers allow us to examine dense matter in even denser, but more importantly significantly hotter matter. This requires a careful reexamination of nuclear and exotic matter transport properties of dense matter. In this talk I will present our work on nuclear and exotic bulk viscosity and Urca like processes in these environments.

"Progress on Electron Scattering from A≤12 Nuclei in the Short-Time-Approximation" presented by Lorenzo Andreoli from Washington University in St. Louis

The Short-time approximation has been developed in the context of quantum Monte Carlo calculations to calculate nuclear responses in nuclei with A > 12. This algorithm exploits a factorization scheme to consistently retain two-body physics, both in two-body currents and correlations.

In this talk, we will present some developments in the calculations of response densities in 12C, as well as recent results for longitudinal and transverse electromagnetic response functions and inclusive cross sections in A=3 nuclei. Using three different factorization schemes based on the same description of nuclear dynamics of the initial target state, we benchmark them among each other and compare them to experimental data.

In addition, we will discuss the removal of the elastic contribution from the response densities calculated in the STA and how that gives a good agreement with experimental data for exchange momenta down to q=300 MeV.