相关论文: Dirac Neutrinos and Primordial Magnetic Fields
The dissipation effects of primordial magnetic fields on the primordial elemental abundances were investigated. When a magnetic field reconnects, its energy is converted to the kinetic energy of charged particles, as observed for solar…
We analyze the influence of neutrino helicity conversion, $\nu_L \to \nu_R$, on the neutrino flux from a supernova caused by the interaction of the Dirac neutrino magnetic moment with a magnetic field. We show that if the neutrino has a…
If different species of neutrinos possess transition magnetic moments, a conversion between species can occur in the Coulomb field of a nucleus. In the case of Dirac neutrinos this corresponds to an active to sterile conversion, whereas in…
Reporting about the formalism with the Dirac equation we describe the dynamics of chiral oscillations for a fermionic particle non-minimally coupling with an external magnetic field. For massive particles, the chirality and helicity quantum…
If neutrinos are Dirac particles the existence of light right-handed neutrinos $\nu_{R}$ is implied. Those would contribute to the effective number of relativistic neutrino species $N_{{\rm eff}}$ in the early Universe. With pure standard…
We consider nucleosynthesis constraints on models which use chiral symmetry breaking as a basis for understanding very small Dirac neutrino masses. We show that present big-bang nucleosynthesis constraints impose a well-defined upper bound…
In view of several conflicting results, we reanalyze the effects of magnetic fields on the primordial nucleosynthesis. In the case the magnetic field is homogeneous over a horizon volume, we show that the main effects of the magnetic field…
Dirac neutrino masses require two distinct neutral Weyl spinors per generation, with a special arrangement of masses and interactions with charged leptons. Once this arrangement is perturbed, lepton number is no longer conserved and…
We analyze the implications of neutrino masses for the magnitude of neutrino magnetic moments. By considering electroweak radiative corrections to the neutrino mass, we derive model-independent naturalness upper bounds on neutrino magnetic…
We calculate the magnetic moment of Dirac type of neutrinos in hot and dense background for different ranges of temperature and chemical potential. The properties of neutrinos are studied in the strong magnetic field where the chemical…
Majorana neutrino oscillations in a magnetic field are considered using the wave packets formalism. The modified Dirac equation for Majorana neutrinos with non-zero transition magnetic moments propagating in a magnetic field is solved…
We consider active-sterile neutrino conversions in the early universe hot plasma in the presence of a random magnetic field generated at the electroweak phase transition. Within a random field domain the magnetization asymmetry of the…
Neutrinos can be pseudo-Dirac in Nature - they can be Majorana fermions while behaving effectively as Dirac fermions. Such scenarios predict active-sterile neutrino oscillations driven by a tiny mass-squared difference $(\delta m^2)$, which…
In this paper, we revisit in detail the effects of primordial magnetic fields on big bang nucleosynthesis (BBN) including a discussion of the magnetic field geometry and the anomalous magnetic moment. The presence of magnetic fields affects…
Using the exact propagators in a constant magnetic field, the neutrino self-energy has been calculated to all orders in the field strength $B$ within the minimal extension of the Weinberg-Salam model with massive Dirac neutrinos. A neutrino…
Massive neutrinos are guaranteed to have nonzero electromagnetic moments and, since there are at least three neutrino species, these dipole moments define a matrix. Here, we estimate the current upper bounds on all independent neutrino…
We quantify the effects of light spin-zero particles with pseudoscalar couplings to leptons and scalar couplings to nucleons on the evolution of solar neutrinos. In this scenario the matter potential sourced by the nucleons in the Sun's…
We develop the approach to the problem of neutrino oscillations in a magnetic field introduced in \cite{Popov:2019nkr} and extend it to the case of three neutrino generations. The theoretical framework suitable for computation of the Dirac…
Spin-flavor oscillations of Dirac neutrinos in matter and a magnetic field are studied using the method of relativistic quantum mechanics. Using the exact solution of the wave equation for a massive neutrino, taking into account external…
Exact solutions of the Dirac--Pauli equation for massive neutrino with anomalous magnetic moment interacting with dense matter and strong electromagnetic field are found. The complete system of neutrino wavefunctions, which show spin…