# Appearance of innermost stable circular orbits of accretion discs around rotating neutron stars

@article{Torok2014AppearanceOI, title={Appearance of innermost stable circular orbits of accretion discs around rotating neutron stars}, author={Gabriel Torok and Martin Urbanec and Karel Ad{\'a}mek and Gabriela Urbancov'a}, journal={Astronomy and Astrophysics}, year={2014}, volume={564} }

The innermost stable cicular orbit (ISCO) of an accretion disc orbiting a neutron star (NS) is often assumed a unique prediction of general relativity. However, it has been argued that ISCO also appears around highly elliptic bodies described by Newtonian theory. In this sense, the behaviour of an ISCO around a rotating oblate neutron star is formed by the interplay between relativis tic and Newtonian effects. Here we briefly explore the consequences of this interp lay using a straightforward…

## 8 Citations

Universal Relations for Innermost Stable Circular Orbits around Rapidly Rotating Neutron Stars

- PhysicsThe Astrophysical Journal
- 2018

We study the innermost stable circular orbit (ISCO) of a test particle around rapidly rotating neutron stars. Based on 12 different nuclear-matter equations of state (EOS), we find numerically two…

Innermost Stable Circular Orbits Around Rotating Compact Stars

- Physics, Geology
- 2017

Orbital motion close to a rotating compact star is largely affected by strong gravity. Location of the innermost stable circular orbit (ISCO) is determined trough interplay between the effects of…

Epicyclic Oscillations in the Hartle–Thorne External Geometry

- PhysicsThe Astrophysical Journal
- 2019

The external Hartle–Thorne geometry, which describes the spacetime outside a slowly rotating compact star, is characterized by the gravitational mass M, angular momentum J, and quadrupole moment Q of…

Rotating stars in relativity

- PhysicsLiving reviews in relativity
- 2017

The latest theoretical understanding of rotating stars in relativity is reviewed and several new sections have been added on equilibria in modified theories of gravity, approximate universal relationships, the one-arm spiral instability, and on analytic solutions for the exterior spacetime.

Test of the string loop oscillation model using kHz quasiperiodic oscillations in a neutron star binary

- Physics
- 2015

The model of current-carrying string loop oscillations is tested to explain the special set of frequencies related to the high-frequency quasiperiodic oscillations (HF QPOs) observed recently in the…

Innermost stable circular orbits of neutron stars in dilatonic-Einstein-Gauss-Bonnet theory

- PhysicsPhysical Review D
- 2019

The innermost stable circular orbits (ISCOs) around rapidly rotating neutron stars are studied in dilatonic Einstein-Gauss-Bonnet theory. Universal relations for properly scaled ISCO properties are…

CONSTRAINING MODELS OF TWIN-PEAK QUASI-PERIODIC OSCILLATIONS WITH REALISTIC NEUTRON STAR EQUATIONS OF STATE

- Physics
- 2016

Twin-peak quasi-periodic oscillations (QPOs) are observed in the X-ray power-density spectra of several accreting low-mass neutron star (NS) binaries. In our previous work we have considered several…

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