Gravity seminar - Konstantinos Gourgouliatos Seminar

Neutron star crusts can be approximated by a highly conducting crystal lattice, where the electric current is carried exclusively by the electron fluid. The evolution of the magnetic field in the crust is mediated through two basic processes: Hall drift which is the advection of the magnetic field by the moving electrons and Ohmic dissipation. I will be discussing the evolution of the magnetic field in neutron star crusts, presenting results of axially symmetric simulations which suggest that while the early evolution is highly sensitive to the initial conditions the endpoint is the "Hall Attractor", a self-similarly decaying state where the electron fluid isorotates with the magnetic field lines, similar to Ferraro's law from solar physics. The observational consequences of these results will be discussed, in particular the influence of the Hall drift to the braking indices of young pulsars if a strong toroidal field is present, and the implications of the Hall Attractor state for middle aged pulsars.