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arXiv · 1010.1951

Resonant radii of kHz quasi-periodic oscillations in Keplerian discs orbiting neutron stars

Zdenek Stuchlik·Andrea Kotrlova·Gabriel Torok
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Abstract

Exchange of dominance between twin kHz quasi-periodic oscillations (QPOs) observed in some low-mass-X-ray-binaries (LMXB) suggests the possibility of a resonance between two oscillatory modes. We study the behaviour of the effective gravitational potential around specific resonant radii, and estimate the role of the higher-order terms governing the non-linear, anharmonic forcing. We discuss the impact it has on the mode amplitude in the linear and non--linear regimes. We also discuss a related possibility of lowering of the neutron star mass estimates from the highest observed QPO frequencies.

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Zdenek Stuchlik, Andrea Kotrlova, Gabriel Torok. 2010-10-10. Resonant radii of kHz quasi-periodic oscillations in Keplerian discs orbiting neutron stars. https://doi.org/10.1051/0004-6361/201015029

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