5 research outputs found
Beta decay in external field and neutrino mass
The results of the investigation of electromagnetic field effects on the
process of beta decay are used for analyzing experimental data on direct
neutrino mass search.Comment: 7 pages, 7 figures, late
Neutron Star Kicks and Asymmetric Supernovae
Observational advances over the last decade have left little doubt that
neutron stars received a large kick velocity (of order a few hundred to a
thousand km/s) at birth. The physical origin of the kicks and the related
supernova asymmetry is one of the central unsolved mysteries of supernova
research. We review the physics of different kick mechanisms, including
hydrodynamically driven, neutrino -- magnetic field driven, and
electromagnetically driven kicks. The viabilities of the different kick
mechanisms are directly related to the other key parameters characterizing
nascent neutron stars, such as the initial magnetic field and the initial spin.
Recent observational constraints on kick mechanisms are also discussed.Comment: 16 pages. Lecture presented at the European Center for Theor. Physics
Workshop on Neutron Star (Trento, Italy, 2000). To be published in "Physics
of Neutron Star Interiors" (Lecture Notes in Physics), ed. D. Blaschke, N.K.
Glendenning and A. Sedrakian (Springer, 2001
Pulsar kicks from a dark-matter sterile neutrino
We show that a sterile neutrino with mass in the 1-20 keV range and a small
mixing with the electron neutrino can simultaneously explain the origin of the
pulsar motions and the dark matter in the universe. An asymmetric neutrino
emission from a hot nascent neutron star can be the explanation of the observed
pulsar velocities. In addition to the pulsar kick mechanism based on resonant
neutrino transitions, we point out a new possibility: an asymmetric
off-resonant emission of sterile neutrinos. The two cases correspond to
different values of the masses and mixing angles. In both cases we identify the
ranges of parameters consistent with the pulsar kick, as well as cosmological
constraints.Comment: 5 pages, 2 figures; final version; discussion and references adde