Pairing effects on neutrino transport in low-density stellar matter

Abstract

We investigate the impact of pairing correlations on neutrino transport in stellar matter. Our analysis is extended to nuclear matter conditions where large density fluctuations develop, associated with the onset of the liquid-vapor phase transition, and clustering phenomena occur. Within a thermodynamical treatment, we show that at moderate temperatures, where pairing effects are still active, the scattering of neutrinos in the nuclear medium is significantly affected by pairing correlations, which increase the neutrino trapping, thus modifying the cooling mechanism, by neutrino emission, of neutron stars.Comment: 5 pages, 3 figure

Finite-temperature infinite matter with effective-field-theory-inspired energy-density functionals

“…The possibility of using these EFT-inspired functionals for describing finite-temperature properties of neutron matter opens new and promising horizons for computations and modeling in scenarios of astrophysical interest. The description of the low-density regime of matter has indeed revealed itself to be extremely important, to properly evaluate a broad spectrum of observables of astrophysical relevance, such as the heat capacity, the thermal conductivity, the neutrino emission, as well as for a precise determination of the crust-core transition point and the related crustal moment of inertia [72][73][74][75][76][77][78][79].…”

Inhomogeneity growth in two-component fermionic systems

“…The splitting of a composite system into fragments under violent perturbations signs the occurrence of the most catastrophic effect produced by largeamplitude fluctuations of the neutron and proton con-tent. Such phenomenology, which is common in heavyion collisions at Fermi energies [13,14], also characterises other fields, like solid-state physics (examples are metal clusters [15,16] or electrons in nanosystems [17]), ultracold atomic gases [18,19] or some areas of astrophysics [20][21][22][23]. The description of the fragmentation process can only be afforded within approaches beyond the mean-field approximation, incorporating the effect of many-body correlations, which induce fluctuations in the evolution of the one-body density.…”

Pairing effects in nuclear pasta phase within the relativistic Thomas-Fermi formalism

“…The specific heat with pairing is expected to enhance the thermalization of neutron star crusts [34]. Some works have argued that neutrino transport and emissivity are also affected by pairing [35,36]. The thermalization could therefore be affected again, as well as the chemical composition during various stages of CCSN and neutron stars.…”

“…The specific heat of the pasta phase was shown to be very sensitive to pairing properties [31,32,33], significantly affecting the thermalization of neutron star crusts [34]. Besides the specific heat, thermalization is also influenced by neutrino emissivity, and pairing effects are expected to be important in this subject too [35,36].…”