Dynamo actions in protoneutron stars

Understanding the long-term evolution of the internal, strong magnetic fields of neutron stars is essential to explain the diversity of the observed phenomenology of neutron stars, characterized by a complex and dynamical magnetic field topology as suggested by the observed bursting mechanisms and the creation of surface hotspots. It has recently been suggested that a turbulent mean-field dynamo action in protoneutron stars can be excited in the early evolutionary phase of the star where strong lepton numbers gradients drive efficient hydrodynamic instabilities. The research project consists in investigating the consequences of a dynamo generated large scale field in such an object to explain the observed “zoo” of pulsar phenomenology. In particular it will be studied for the first time, the long term evolution of a dynamo-generated crustal field in magnetars and in isolated neutron stars.