S E M I N A R I

Departament d'Astronomia i Astrofísica
Universitat de València

    Nonlinear damping of neutron star oscillations

Wolfgang Kastaun

Albert Einstein Institut (Alemanya)


Seminari del departament d'Astronomia i Astrofísica

Divendres 24 febrer 2012

15:00


Resum

Oscillations of neutron stars are a possible source of detectable gravitational waves due to the existence of a gravitational-rotational instability which transfers energy from the rotation of a star into gravitational waves and oscillation energy. There are however several effects that could suppress the growth of those instabilities already at low amplitudes, e.g. viscosity, mode coupling, or superfluidity effects. Those mechanisms depend on physical parameters not exactly known and/or are difficult to estimate even for given parameters due to the long timescales involved. We instead investigated generic hydrodynamic effects active at very high amplitudes, such as shock formation or breaking of surface waves, in order to provide absolute upper limits on the gravitational wave luminosity of oscillating neutron stars.