Thermal conductivity of an ultracold Fermi gas in the BCS-BEC crossover

Recent experiments on sound waves in a unitary Fermi gas reveal many transport properties about strongly interacting fermions. Sound propagates through the coupling of momentum and heat transport, and attenuates strongly with the presence of a phase transition. In this work, focusing on the temperature regimes near and below the superfluid critical temperature $$T_c$$ T c in the BCS-BEC crossover, we present a Kubo-based microscopic calculation of thermal conductivity $$\kappa$$ κ , which has not attracted much attention compared to the shear viscosity. Our approach primarily addresses the contributions of the fermionic quasiparticles to thermal transport and our results return to the kinetic descriptions at high temperatures. $$\kappa$$ κ drops upon crossing the pseudogap temperature $$T^*$$ T ∗ , and its temperature dependence changes below $$T_c$$ T c . The drops become more pronounced on the weakly coupled BCS side, where the Pauli blocking causes the upturn of $$\kappa$$ κ above $$T^*$$ T ∗ . Our calculations fit well with the sound measurement on the damping rate.

Pairing effects on neutron elastic scattering at low-energies

For the first time, a realistic microscopic calculation for low-energy neutron-nucleus elastic scattering off open-shell nuclei is carried out within the framework of particle-vibration coupling (PVC). In this study, the pairing correlations of the ground state are taken into account. The dependence of the angular distributions on the pairing gaps is discussed.

Pairing effects on neutron elastic scattering at low-energies

For the first time, a realistic microscopic calculation for low-energy neutron-nucleus elastic scattering off open-shell nuclei is carried out within the framework of particle-vibration coupling (PVC). In this study, the pairing correlations of the ground state are taken into account. The dependence of the angular distributions on the pairing gaps have been discussed.

Microscopic Calculation of Fission Fragment Distributions in Actinides

The simulation of independent and cumulative yields requires precise knowledge of the initial conditions of the fission fragments immediately after scission. In this paper, we use a quantum-mechanical description of fission dynamics to extract the initial mass distribution of fission fragments for the neutron-induced fission of the two major actinides 239 Pu and 235 U, both for thermal fission and as a function of the incident neutron energy.