Astronomy and Astrophysics – Astrophysics
Scientific paper
2001-05-24
Astronomy and Astrophysics
Astrophysics
45 pages, 3 figures, Astrophysical Journal, in press
Scientific paper
10.1086/322320
We consider the amplification and transport of a magnetic field in the collapsed core of a massive star, including both the region between the neutrinosphere and the shock, and the central, opaque core. An analytical argument explains why rapid convective overturns persist within a newly formed neutron star for roughly 10 seconds ($> 10^3$ overturns), consistent with recent numerical models. A dynamical balance between turbulent and magnetic stresses within this convective layer corresponds to flux densities in excess of $10^{15}$G. Material accreting onto the core is heated by neutrinos and also becomes strongly convective. We compare the expected magnetic stresses in this convective `gain layer' with those deep inside the neutron core. Buoyant motions of magnetized fluid are greatly aided by the intense neutrino flux. We calculate the transport rate through a medium containing free neutrons protons, and electrons, in the limiting cases of degenerate or non-degenerate nucleons. Fields stronger than $\sim 10^{13}$ G are able to rise through the outer degenerate layers of the neutron core during the last stages of Kelvin-Helmholtz cooling (up to 10 seconds post-collapse), even though these layers have become stable to convection. We also find the equilibrium shape of a thin magnetic flux rope in the dense hydrostatic atmosphere of the neutron star, along with the critical separation of the footpoints above which the rope undergoes unlimited expansion against gravity. The implications of these results for pulsar magnetism are summarized, and applied to the case of late fallback over the first 1,000-10,000 s of the life of a neutron star
Murray Norman
Thompson Christopher
No associations
LandOfFree
Transport of Magnetic Fields in Convective, Accreting Supernova Cores does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Transport of Magnetic Fields in Convective, Accreting Supernova Cores, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transport of Magnetic Fields in Convective, Accreting Supernova Cores will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-98035