B. I. Goryachev | Searcharxiv

arXiv2010

The Extreme Energies Lines in the Solar Neutrino Spectrum

Tritium chain of the hydrogen cycle in the Sun including reactions ^3He(e^-,ν_(e))^(3)H(p,γ)^(4)He is considered. At the distance of 1 a.u. the flux of tritium neutrinos is equal to 8.1\cdot 10^(4) cm^(-2)s^(-1). It is an order of magnitude higher than the flux of the (hep)-neutrinos. Radial distribution of ^(3)H-neutrinos yield inside the Sun and their energy spectrum which has a form of line at the energy of (2,5 ÷ 3,0) keV are calculated. The flux of thermal tritium neutrinos is accompanied by a very weak flux of antineutrinos (~ 10^(3) cm^(-2)year^(-1)) with energy lower than 18,6 keV. These antineutrinos are produced during Urca processes ^3He<=>^3H. The flux of the neutrinos of maximum possible energy (line 19,8 MeV) produced due to the (heep)-reaction (related to the (hep)-process) is estimated

astro-ph.SR↗

arXiv2007

Statistical analysis of neutrino events from SN1987A neutrino burst: estimation of the electron antineutrino mass

The method of the statistical sample moments was used for the analysis of neutrino events from SN1987A burst in Cherenkov detectors. In particular the coefficients of correlation $Q(E,t)$ between the energies $E$ of electron antineutrinos $\bar ν_e$ emitted by star and the ejection instants $t$ of $\bar ν_e$ for neutrino events recorded by Cherenkov water detectors of KII and IMB collaborations were calculated. $Q(E,t)$ values depend on the assumed mass of $\bar ν_e$. Modern model of the gravitational stellar core collapse with an accretion phase predicts the low level of such correlation $ $ averaged with respect to neutrino burst. On condition that empirical $Q(E,t)$ values equal the theoretical model quantities $ $ one can obtain $22\pm10 eV/c^{2}$ as an estimate of the nonzero $\bar ν_e$ mass. The error of this estimate implies that $\bar ν_e$ mass less than $2 eV/c^2$ is unlikely. The laboratry data of the tritium $β$-decay agree adequately with the presented astrophysical estimate provided that the anomalous structure near the end point of $β$-spectrum is taken into account.

astro-ph↗