相关论文: Cosmic Neutrino Background as a Ferromagnet
The explanation of the observed galactic magnetic fields may require the existence of a primordial magnetic field. Such a field may arise during the early cosmological phase transitions, or because of other particle physics related…
A model of the ferromagnetic origin of magnetic fields of neutron stars is considered. In this model, the magnetic phase transition occurs inside the core of neutron stars soon after formation. However, owing to the high electrical…
Earlier de Sabbata and Gasperini have shown that neutrinos oscillation which gives them a mass can be induced by torsion. More recently Enqvist et al have shown that it is possible to use massive neutrinos BBN magnetic fields to seed…
The observed galactic magnetic fields may have a primordial origin. I briefly review the observations, their interpretation in terms of the dynamo theory, and the current limits on cosmological magnetic fields. Several possible mechanisms…
It is known that if neutrino is a Dirac fermion with magnetic moment, then \nu_L -> \nu_R -> \nu_L transition of supernova neutrinos may occur. The first stage of such transition is due to the neutrino spin flip inside the hot dense…
If massive neutrinos possess magnetic moments, they can undergo spin flip in a magnetic field. The magnetic fields needed for a meaningful measurement of neutrino moments could be very high and may occur in astronomical objects such as some…
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…
Possible consequences of ferromagnetic transition in dense matter suggested recently by Kutschera and W{\'o}jcik, for the magnetic properties of neutron stars, are studied. Specific model of dense matter, in which a small admixture of…
It is shown explicitly that a ferromagnetic transition of neutron star (NS) / proto-neutron star (PNS) matter in the $\beta$-equilibrium condition with $\sigma-\omega-\rho$ exchange type of mean field approximation can actually occur if and…
We consider the generation and evolution of magnetic field in a primordial plasma at temperature T < 1 MeV in presence of asymmetric neutrino background i.e. the number densities of right- handed and left-handed neutrinos are not same.…
We study the physical conditions for the occurrence of ferromagnetic instability in a neutral plasma of fermions. We consider a system of two species $M$ and $Y$ which are oppositely charged under a local $U(1)_{X}$, with $M$ much lighter…
We show that a primeval seed magnetic field arises due to spin-degeneracy breaking of fermions caused by the dragging of inertial frames in the curved spacetime of rotating astrophysical bodies. This seed magnetic field would arise even due…
Parity violation and its effects for neutrinos in astrophysical contexts have been considered earlier in pioneering papers of Hawking and Vilenkin. But because even the largest magnetic moments predicted by physics beyond the Standard Model…
Primordial magnetic fields and massive neutrinos can leave an interesting signal in the CMB temperature and polarization. We perform a systematic analysis of general perturbations in the radiation-dominated universe, accounting for any…
It is argued that large scale cosmic magnetic field could be generated in the primeval plasma slightly before hydrogen recombination. Non-zero vorticity, necessary for that, might be created by the photon diffusion in the second order in…
Neutrino interactions play a central role in transport and flavor evolution in the ejecta of binary neutron star mergers. Simulations suggest that neutron star mergers may produce magnetic fields as strong as $10^{17}$ G, but computational…
We point out that the lower bound on the primordial magnetic field required to seed the galactic dynamo is significantly relaxed in an open universe or in a universe with a positive cosmological constant. It is shown that, for reasonable…
We study the generation of strong magnetic fields in magnetars and in the early universe. For this purpose we calculate the antisymmetric contribution to the photon polarization tensor in a medium consisting of an electron-positron plasma…
We derive general expressions for the neutrino dispersion relation in a magnetized plasma with a wide range of temperatures, chemical potentials, and magnetic field strengths. If the electron and proton chemical potentials vanish, as in the…
We explore the impact of magnetic field on neutrino-matter interactions in core-collapse supernova. We first derive the modified source terms for neutrino-nucleon scattering and neutrino absorption and emission processes in the moment…