Origin of Reactor Antineutrino Anomaly
Abstract
The reactor antineutrino anomaly, discovered in 2011, means a noticeable difference between the observed rate of inverse beta decays and the expected (theoretical) rate of such processes based on the measurement of the spectra of electrons in beta decay of $^{235}$U, $^{239}$Pu, $^{241}$Pu, and $^{238}$U nuclei and their subsequent conversion into right-handed antineutrino spectra. This paper provides a rationale for the fact that both right-handed and left-handed antineutrinos are produced in beta decays of nuclei. But the conversion procedure in any case assigns a right-handed antineutrino to each electron, which leads to the superiority of the theoretical rate of inverse beta decays over the experimental one. The right-handed antineutrino is produced in the mode of beta decay of the nucleus due to the standard electroweak interaction. The left-handed antineutrino appears in the mode caused by the existence of a interaction, the carrier of which is a massless pseudoscalar boson having a Yukawa coupling with the electron neutrino and nucleons. The emission of such a boson from a virtual right-handed antineutrino converts it into a free left-handed antineutrino.