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The physics of kHz QPOs---strong gravity's coupled anharmonic oscillators

Wlodek Kluzniak·Marek Artur Abramowicz
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Abstract

We explain the origin of the puzzling high frequency peaks (QPOs) in the variability power spectra of accreting neutron stars and black holes as a non-linear 1:2 or 1:3 resonance between orbital and radial epicyclic motion. These resonances are present because the gravitational field deviates strongly from a Newtonian 1/r potential. Our theory agrees with the recently reported observations of two QPOs, at 300 Hz and 450 Hz, in the black hole candidate GRO J1655-40.

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Wlodek Kluzniak, Marek Artur Abramowicz. 2001-05-03. The physics of kHz QPOs---strong gravity's coupled anharmonic oscillators. https://arxiv.org/abs/astro-ph/0105057

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