The Effects of Superfluidity on the Oscillation Modes of Neutron Stars

<p> Oscillating single neutron stars are considered to be important quasi-continuous sources for gravitational wave emission and detection at the Laser Interferometer Gravitational-Wave Observatory (LIGO). In order to detect these oscillations above the noise level in the detector, LIGO data must be compared to theoretical templates of the signal, which means predicting the signal amplitude and frequency range. In this thesis, we compute the two most important eigenfrequencies of superfluid neutron stars where the signal might be peaked. To calculate this spectrum, we first construct the background structure of the neutron star using realistic microscopic models of dense and interacting nuclear matter. For this purpose, we use the CompOSE database which provides an array of such models with thermodynamically consistent interpolation. The fluid pertubation equations of the equilibrium configuration, including superfluidity in a two-fluid model, are solved numerically in the non-relativistic limit, yielding the eigenfrequencies upon imposing suitable boundary conditions. We find that the modes of the superfluid star support modes that are very close to the corresponding normal fluid star, but there also appear one or two purely superfluid modes, the lower one of which is intermediate between the two lowest order modes of the normal fluid. Thus, in the event that these oscillation modes can be observed, we can confirm the theoretical prediction of neutron superfluidity in neutron stars. A part of the results presented in this thesis have been published as a proceedings article in Jaikumar, Monroy and Klaehn, <i> Universe</i> 4, 58 (2018).</p><p>

Identiferoai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:10830502
Date18 September 2018
CreatorsMonroy, Raphael R.
PublisherCalifornia State University, Long Beach
Source SetsProQuest.com
LanguageEnglish
Detected LanguageEnglish
Typethesis

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