Neutrino-heated winds from rotating proto-magnetars
Abstract
We calculate the steady-state properties of neutrino-driven winds from strongly magnetized, rotating proto-neutron stars (`proto-magnetars') under the assumption that the outflow geometry is set by the force-free magnetic field of an aligned dipole. Our goal is to assess proto-magnetars as sites of r-process nucleosynthesis and gamma-ray burst engines. One dimensional solutions calculated along flux tubes corresponding to different polar field lines are stitched together to determine the global properties of the flow at a given neutrino luminosity and rotation period. Proto-magnetars with rotation periods of P~2-5 ms are shown to produce outflows more favorable for the production of third-peak r-process nuclei due to their much shorter expansion times through the seed nucleus formation region, yet only moderately lower entropies, as compared to normal spherical PNS winds. Proto-magnetars with moderately rapid birth periods P~3-5 ms may thus represent a promising Galactic r-process site which is compatible with a variety of other observations, including the recent discovery of possible magnetar-powered supernovae in metal poor galaxies. We also confirm previous results that the outflows from proto-magnetars with P~1-2 ms can achieve maximum Lorentz factors Gamma ~ 100-1000 in the range necessary to power gamma-ray bursts (GRBs). The implications of GRB jets with a heavy nuclei-dominated composition as sources of ultra-high energy cosmic rays are also addressed.
Keywords
Cite
@article{arxiv.1405.7043,
title = {Neutrino-heated winds from rotating proto-magnetars},
author = {Andrey D. Vlasov and Brian D. Metzger and Todd A. Thompson},
journal= {arXiv preprint arXiv:1405.7043},
year = {2015}
}
Comments
15 pages, 14 figures, 4 tables, submitted to MNRAS