Talk detail

Participant	Boshkayev, Kuantay
Institution	Al-Farabi Kazakh National University - Al-Farabi avenue, 71 - Almaty - - Kazakhstan

Session	WD1-3	Accepted		Order	Time
Talk	Oral abstract	Title	Mass-radius relations of white dwarfs at finite temperatures
Coauthors
Abstract	In this work we illustrate the mass-radius relation of cold static and rotating white dwarfs (WDs) for the Chandrasekhar equation of state (EOS) and compare them with the observed masses and radii of WDs from the Sloan Digital Sky Survey Data Release 4 (SDSS-E06 catalog). We show that for masses 0.7−0.8 solar masses the deviations from the degenerate treatments are already evident. It is natural to expect that such deviations could be related to the neglected effects of finite temperatures on the structure of the white dwarf. Therefore, the finite-temperature effects on the EOS and, consequently, on the mass-radius relations of the white dwarf are of high importance. Here we extend the EOS by introducing the effects of finite temperatures and use it to construct equilibrium configurations of white dwarfs at finite temperatures.
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Session	NS4	Accepted		Order	Time
Talk	Oral abstract	Title	Main parameters of neutron stars from quasi-periodic oscillations in low mass X-ray binaries
Coauthors
Abstract	We consider the kilohertz quasi-periodic oscillations of low-mass X-ray binaries within the Hartle-Thorne spacetime. We show that the interpretation of the epicyclic frequencies of this spacetime with the observed kilohertz quasi-periodic oscillations, within the Relativistic Precession Model, allows to extract the total mass M, angular momentum J, and quadrupole moment Q of the compact object in a low-mass X-ray binary. We exemplify this fact by analyzing the data of the Z -source GX 5-1. We show that the extracted multipole structure of the compact component of this source deviates from the one expected from a Kerr black hole and instead it points to a neutron star explanation.
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Session	BN4	Accepted		Order	Time
Talk	Oral abstract	Title	Induced Compression of White Dwarfs by Angular Momentum Loss
Coauthors
Abstract	We consider isolated general relativistic uniformly-rotating white dwarfs which lose angular momentum due to magnetic dipole braking. We explicitly show for selected constant mass sequences how main parameters of white dwarfs such as the central density, mean radius, moment of inertia and angular velocity change with time by fulﬁlling all stability criteria of the general relativistic uniformly-rotating conﬁgurations.
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