Adiabatic index of dense matter and damping of neutron star pulsations
N. Copernicus Astronomical Center, Bartycka 18, 00-716 Warszawa, Poland e-mail: email@example.com
2 Ioffe Physical Technical Institute, Politekhnicheskaya 26, 194021 St.-Petersburg, Russia e-mail: firstname.lastname@example.org;email@example.com
Corresponding author: P. Haensel, firstname.lastname@example.org
Accepted: 30 July 2002
The adiabatic index for perturbations of dense matter is studied under various physical conditions which can prevail in neutron star cores. The dependence of on the composition of matter (in particular, on the presence of hyperons), on the stellar pulsation amplitude, and on the baryon superfluidity is analyzed. Timescales of damping of stellar pulsations are estimated at different compositions, temperatures, and pulsation amplitudes. Damping of pulsations by bulk viscosity in the neutron-star cores can prevent the stars to pulsate with relative amplitudes (depending on the composition of matter).
Key words: stars: neutron / dense matter / oscillations
© ESO, 2002