Neutrino processesvv̅→e^-e⁺andv→ve^-e⁺in a strong magnetic field

Abstract

Abstract. The processes of neutrino production of electron-positron pairs, νν → e − e + and ν → νe − e + , in a magnetic field of arbitrary strength, where electrons and positrons can be created in the states corresponding to excited Landau levels, are analysed. The results can be applied for calculating the efficiency of the electron-positron plasma production by neutrinos in the conditions of the Kerr black hole accretion disc considered by experts as the most possible source of a short cosmological gamma burst. IntroductionAn intense electromagnetic field makes possible the processes which are forbidden in a vacuum such as the neutrino production of an electron-positron pair ν → νe − e + . The list of papers devoted to an analysis of this process and the collection of the results obtained could be found e.g. in [1]. In most cases, calculations of this kind were made either in the crossed field approximation, or in the limit of a superstrong field much greater than the critical value of B e = m 2 e /e 4.41 × 10 13 G (we use natural units c =h = k B = 1), when the electrons and positrons are born in states corresponding to the ground Landau level. However, there exist physical situations of the so-called moderately strong magnetic field, p 2 ⊥ ≥ eB m 2 e , when electrons and positrons mainly occupy the ground Landau level, however, a noticeable fraction may be produced at the next levels.The indicated hierarchy of physical parameters corresponds to the conditions of the Kerr black hole accretion disk, regarded by experts as the most likely source of a short cosmological gamma-ray burst. The disc is a source of copious neutrinos and anti-neutrinos, which partially annihilate above the disc and turn into e ∓ pairs, νν → e − e + . This process was proposed and investigated in many details (for the list of references see e.g. [2,3]) as a possible mechanism for creating relativistic, e ∓ -dominated jets that could power observed gamma-ray bursts. In [2], in addition to νν annihilation, the contribution of the magnetic field-induced process ν → νe − e + to the neutrino energy deposition rate around the black hole was also included for the first time. The authors [2] concluded in part, that the process ν → νe − e + could dominate over the basic process νν → e − e + . They used the result for the energy deposition rate in the process ν → νe − e + obtained in [4,5] in the crossed field limit, while in those physical conditions (B to 180 B e , E ν to 25 MeV) the approximation of a crossed field is poorly applicable (as well as

Neutrino-electron scattering in a dense magnetized plasma

“…It should be noted, that, in contrast to calculations of Refs. [5,6], in the present case no upper limits arise on the Landau level numbers , n from kinematics, and the suppression of the large number contributions is provided by the distribution functions of initial and final electrons.…”

Neutrino-electron scattering in a dense strongly magnetized plasma

“…It should be noted, that, in contrast to calculations of Refs. [11,12], in the present case no upper limits arise on the Landau level numbers , n from kinematics, and the suppression of the large number contributions is provided by the distribution functions of initial and final electrons.…”