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arXiv · 1602.07869

Thermal QRPA with Skyrme interactions and supernova neutral-current neutrino-nucleus reactions

Alan A. Dzhioev·A. I. Vdovin·G. Martínez-Pinedo·J. Wambach·Ch. Stoyanov
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Abstract

The Thermal Quasiparticle Random-Phase Approximation is combined with the Skyrme energy density functional method (Skyrme-TQRPA) to study the response of a hot nucleus to an external perturbation. For the sample nuclei, $^{56}$Fe and $^{82}$Ge, the Skyrme-TQRPA is applied to analyze thermal effects on the strength function of charge-neutral Gamow-Teller transitions which dominate neutrino-nucleus reactions at $E_ν\lesssim 20$~MeV. For the relevant supernova temperatures we calculate the cross sections for inelastic neutrino scattering. We also apply the method to examine the rate of neutrino-antineutrino pair emission by hot nuclei. The cross sections and rates are compared with those obtained earlier from the TQRPA calculations based on the phenomenological Quasiparticle-Phonon Model Hamiltonian. For inelastic neutrino scattering on $^{56}$Fe we also compare the Skyrme-TQRPA results to those obtained earlier from a hybrid approach that combines shell-model and RPA calculations.

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Alan A. Dzhioev, A. I. Vdovin, G. Martínez-Pinedo, J. Wambach, Ch. Stoyanov. 2016-07-19. Thermal QRPA with Skyrme interactions and supernova neutral-current neutrino-nucleus reactions. https://doi.org/10.1103/physrevc.94.015805

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