Magnetic Fields and Stellar Evolution

Stellar Evolution with Rotation and Magnetic Fields

We examine the generation of a magnetic field in a solar-like star and its effects on the internal distribution of the angular velocity. We suggest that the evolution of a rotating star with magnetic fields leads to an equilibrium value of the differential rotation. This equilibrium is determined by the magnetic coupling, which favours a constant rotation profile, and meridional circulation whi...

Searching for links between magnetic fields and stellar evolution

Context. The evolution of magnetic fields in Ap stars during the main sequence phase is presently mostly unconstrained by observation because of the difficulty of assigning accurate ages to known field Ap stars. Aims. We are carrying out a large survey of magnetic fields in cluster Ap stars with the goal of obtaining a sample of these stars with well-determined ages. In this paper we analyse th...

Life Cycles of Magnetic Fields in Stellar Evolution

Stellar evolution with rotation and magnetic fields: I. The relative importance of rotational and magnetic effects

We compare the current effects of rotation in stellar evolution to those of the magnetic field created by the Tayler instability. In stellar regions, where magnetic field can be generated by the dynamo due to differential rotation (Spruit 2002), we find that the growth rate of the magnetic instability is much faster than for the thermal instability. Thus, meridional circulation is negligible wi...

Magnetic Fields in High-Density Stellar Matter

I briefly review some aspects of the effect of magnetic fields in the high density regime relevant to neutron stars, focusing mainly on compact star structure and composition, superconductivity, combustion processes, and gamma ray bursts. THE “MAGNETIC FIELD” OF “NEUTRON STARS” A large body of evidence now identifies the presence of strong magnetic fields at (or very near) the surface of neutro...