Neutrino spin oscillations in external fields in curved spacetime

Abstract

We study spin oscillations of massive Dirac neutrinos in background matter, electromagnetic and gravitational fields. First, using the Dirac equation for a neutrino interacting with the external fields in curved spacetime, we rederive the quasiclassical equation for the neutrino spin evolution, which was proposed previously basing on principles of the general covariance. Then, we apply this result for the description of neutrino spin oscillations in nonmoving and unpolarized matter under the influence of a constant transverse magnetic field and a gravitational wave. We derive the effective Schrödinger equation for neutrino oscillations in these external fields and solve it numerically. Choosing realistic parameters of external fields, we show that the parametric resonance can take place in spin oscillations of low energy neutrinos. Some astrophysical applications are briefly discussed. * maxdvo@izmiran.ru

Spin effects in neutrino gravitational scattering

“…14, the influence of the neutrino interaction with background matter on its spin evolution in curved spacetime was studied in Refs. [6,7]. It results in the appearance of the additional components of the vector Ω g in Eq.…”

“…Here F is given in Eq. (7). Equation (16) should be supplied with the initial condition ψ T 8 " p1, 0q, which means that all incoming neutrinos are left polarized.…”

“…Neutrino spin oscillations in various external fields in curved spacetime were studied in Refs. [5][6][7] We considered both static metrics and a time dependent backgrounds, like a gravitational wave. Note that the evolution of the fermion spin in curved spacetime was analyzed in Refs.…”

“…In this our work, we continue our studies of neutrino spin oscillations in Refs. [5][6][7]. We start in Sec.…”

Neutrino oscillations in gravitational waves

“…The transition probability for ν − → ν + oscillations, based on the numerical solution of equation (6), is shown in figure 1. We have chosen the parameters of a neutrino and external fields corresponding to a particle propagating in the vicinity of merging black holes (BHs), surrounded by a dense magnetized accretion disk [4].…”