Vendredi 07 novembre 2014 à 14h15
Auditoire Stueckelberg, Ecole de Physique

Neutron Stars: Instabilities driven by rotation and/or magnetic fields and emission of gravitational waves

Kostas Kokkotas, University of Tubingen

Neutron stars are cosmic laboratories of extreme physics, governed by the interplay between gravity and the strong nuclear force. The multifaceted nature of neutron stars makes them ideal test-beds for breakthroughs in astrophysics, gravitational physics, and nuclear physics. Their high compactness implies a huge amount of gravitational energy available to be tapped and converted into a number of different forms. It is not surprising, therefore, that neutron stars are seen as prime sources for the emission of gravitational waves, as well as radio, gamma and x-rays. The imminent detection of gravitational waves is expected to provide a unique opportunity for making a leap forward in our understanding of neutron star physics. Instabilities driven by a neutron star's extreme magnetic field and rotation are of special importance since they can lead to a powerful emission of both electromagnetic and gravitational radiation. The emitted signal carries information about the salient properties of the object such as the equation of state of its matter, its cooling rate, and the presence of superfluidity and superconductivity. As a result, a proper modelling of neutron stars can lead to breakthroughs in our understanding of supranuclear matter. In this presentation we will discuss the latest results on neutron star instabilities associated with the magnetic field and rotation and assess the chance of the emitted gravitational waves being detected in the next five years, as well as the possibility of revealing their elusive equation of state.