Pulsar acceleration by asymmetric emission of sterile neutrinos

Abstract

A convincing explanation for the observed pulsar large peculiar velocities is still missing. We argue that any viable particle physics solution would most likely involve the resonant production of a non-interacting neutrino ${\nu }_s$ of mass $m_{{\nu }_s}\sim 20$--50 keV. We propose a model where anisotropic magnetic field configurations strongly bias the resonant spin flavour precession of tau antineutrinos into ${\nu }_s$. For internal magnetic fields $B_{int}\text{gsim}10^{15}$ G a ${\bar{\nu }}_{\tau }$-${\nu }_s$ transition magnetic moment of the order of $10^{-12}$ Bohr magnetons is required. The asymmetric emission of ${\nu }_s$ from the core can produce sizeable natal kicks and account for recoil velocities of several hundred kilometers per second.

Comments: 14 pages, AASTEX, 2 figures (uses epsfig). Minor typos corrected. Added acknowledgments to the funding institutes BID and Colciencias