Overview:
This page contains the nuclear neutrino spectral data described in the paper by Misch, Sun, and Fuller, Ap. J. 852 (2018) 43 arXiv:1708.08792.

This database contains shell model calculations of neutrino energy spectra produced in astrophysical conditions by 70 sd-shell nuclei over the mass number range A=21-35. It includes electron-flavored neutrinos and antineutrinos produced from charged lepton captures and decays (charged current), and neutrino pairs of all flavors from neutral current nuclear deexcitation, wherein an excited nucleus relaxes by emitting a neutrino pair (neutral current). The neutral current spectra should be interpreted this way: they are the sum of all three known neutrino flavors (so the contribution of a single flavor is one third of the tabulated values), and they are identical for neutrinos and antineutrinos (the tabulated values represent neutrinos and antineutrinos separately, not the sum).

Nuclear shell model considerations:
The full sd-shell model space was used to compute initial nuclear states up to 20 MeV excitation with transitions to final states up to 35-40 MeV, employing a modification of the Brink-Axel hypothesis to handle high temperature population factors and the nuclear partition functions. The sd-shell model space consists of an inert oxygen-16 "core" that does not participate in nuclear transitions and a "valence space" of 12 proton states and 12 neutron states that can each be occupied or unoccupied. Nuclear eigenstates are constructed from basis states consisting of configurations of proton and neutron single particle state occupations. To ensure a sufficiently large basis to reasonably represent reality, only nuclear transitions where both the parent and daughter nuclei have at least 2 and at most 10 valence nucleons of each species are included; that is, both the parent and daughter nuclei must have at least 10 and at most 18 protons, and at least 10 and at most 18 neutrons. Because both parent and daughter nuclei must satisfy this requirement, there are edge-case nuclei with charged current neutrino spectra for electron capture and positron decay, but not positron capture or electron decay (and vice versa).

Tables:
The charged current spectra are tabulated on the Fuller-Fowler-Newman temperature-density grid (shown below); the neutral current spectra do not depend on density, so they are tabulated separately as functions of only temperature. Both sets of tables are listed as spectral densities per baryon (neutrinos / second baryon MeV), so the total output spectrum of the nucleus is this value times the number of baryons in the nucleus. In principle, the number of neutrinos in each bin is the spectral density times the bin width for sufficiently narrow bins. However, as discussed below, this interpretation is highly suspect when there are sharp features in the spectra, so caution is advised when using these spectra to compute total neutrino production and energy loss rates. The charged current spectra are given at 0.5 MeV neutrino energy resolution, and the neutral current spectra at 0.1 MeV resolution. Unstable nuclei have extremely sharp peaks in their capture spectra at low temperature and density; to ensure that they are represented, additional neutrino energy points are included near those peaks.

The temperatures are given in MeV, but these have been rounded to 4 decimal places; the T9 (10⁹ Kelvin) values shown below are the exact values used in the calculations. The conversion is as follows: T (MeV) = T9 * 10⁹ * Boltzmann's constant (8.6173324 * 10^-11 MeV/K). Rho Ye is the density (rho, g/cm³) times the electron fraction (Ye, electron-to-baryon ratio of the environment). The FFN temperature-density grid consists of every combination of temperature and density from the values below.
T9 = 0.01, 0.1, 0.2, 0.4, 0.7, 1.0, 1.5, 2.0, 3.0, 5.0, 10.0, 30.0
T (MeV) = 0.0009, 0.0086, 0.0172, 0.0345, 0.0603, 0.0862, 0.1293, 0.1723, 0.2585, 0.4309, 0.8617, 2.5852
rho*Ye (g/cm³) = 10¹, 10², ... 10¹¹

The columns in the charged current tables are:
rho Ye: density times electron fraction in g/cm³
temp: temperature in mega electron volts (MeV)
energy: neutrino energy (MeV)
e- cap: neutrino spectral density from electron capture
e+ dec: neutrino spectral density from positron emission
e+ cap: antineutrino spectral density from positron capture
e- dec: antineutrino spectral density from electron emission.

The columns in the neutral current tables are:
temp: temperature (MeV)
energy: neutrino energy (MeV)
spectrum: (anti)neutrino spectral density summed over all flavors.

Warning:
Where the spectra are sufficiently smooth, they can be integrated using a simple rectangular or trapezoidal method to obtain the total neutrino production and energy loss rates. This condition of smoothness is met by the neutral current spectra and most of the time by the charged lepton emission spectra. It is met by all processes at sufficiently high temperature and density, but low temperature and/or density capture spectra on unstable nuclei fail this condition due to their sharp peaks. The simplest remedy is to simply scale the spectra according to the prescription in the paper detailing the calculation of these spectra.