Neutrino and anti-neutrino energy loss rates due to iron isotopes suitable for core-collapse simulations

Abstract

Accurate estimate of neutrino energy loss rates are needed for the study of the late stages of the stellar evolution, in particular for cooling of neutron stars and white dwarfs. The energy spectra of neutrinos and antineutrinos arriving at the Earth can also provide useful information on the primary neutrino fluxes as well as neutrino mixing scenario (it is to be noted that these supernova neutrinos are emitted after the supernova explosion which is a much later stage of stellar evolution than that considered in this paper). Recently an improved microscopic calculation of weak-interaction mediated rates for iron isotopes was introduced using the proton-neutron quasiparticle random phase approximation (pn-QRPA) theory. Here I present for the first time the fine-grid calculation of the neutrino and anti-neutrino energy loss rates due to $^{54,55,56}$Fe in stellar matter. In the core of massive stars isotopes of iron, $^{54,55,56}$Fe, are considered to be key players in decreasing the electron-to-baryon ratio ($Y_{e}$) mainly via electron capture on these nuclide. Core-collapse simulators may find this calculation suitable for interpolation purposes and for necessary incorporation in the stellar evolution codes. The calculated cooling rates are also compared with previous calculations.Comment: 12 pages, 3 figures and 1 table. arXiv admin note: text overlap with arXiv:1108.4569, arXiv:1203.4675, arXiv:1203.434