2025/10/08 by Martínez-Miravé, Pablo, Tamborra, Irene
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE) #High Energy Physics - Experiment (hep-ex) #High Energy Physics - Phenomenology (hep-ph) #Solar and Stellar Astrophysics (astro-ph.SR)
paper · doi:10.48550/arxiv.2510.07399
Neutrinos are produced during stellar evolution by means of thermal and thermonuclear processes. We model the cumulative neutrino flux expected at Earth from all stars in the Milky Way: the Galactic stellar neutrino flux (GSνF). We account for the star formation history of our Galaxy and reconstruct the spatial distribution of Galactic stars by means of a random sampling procedure based on Gaia Data Release 2. We use the stellar evolution code MESA to compute the neutrino emission for a suite of stellar models with solar metallicity and zero-age-main-sequence mass between 0.08M_\odot and 100 M_\odot, from their pre-main sequence phase to their final fates. We then reconstruct the evolution of the neutrino spectral energy distribution for each stellar model in our suite. The GSνF lies between O(1) keV and O(10) MeV, with thermal (thermonuclear) processes responsible for shaping neutrino emission at energies smaller (larger) than 0.1 MeV. Stars with mass larger than O(1 M_\odot), located in the thin disk of the Galaxy, provide the largest contribution to the GSνF. Moreover, most of the GSνF originates from stars distant from Earth about 5-10 kpc, implying that a large fraction of stellar neutrinos can reach us from the Galactic Center. Solar neutrinos and the diffuse supernova neutrino background have energies comparable to those of the GSνF, challenging the detection of the latter. However, directional information of solar neutrino and GSνF events, together with the annual modulation of the solar neutrino flux, could facilitate the GSνF detection; this will kick off a new era for low-energy neutrino astronomy, also providing a novel probe to discover New Physics.