Gravitational excitation of high frequency QPOs

Abstract

We discuss the possibility that high-frequency QPOs in neutron-star binary systems may result from forced resonant oscillations of matter in the innermost parts of the accretion disc, excited by gravitational perturbations coming from asymmetries of the neutron star or from the companion star. We find that neutron-star asymmetries could, in principle, be effective for inducing both radial and vertical oscillations of relevant amplitude while the binary companion might possibly produce significant radial oscillations but not vertical ones. Misaligned neutron-star quadrupole moments of a size advocated elsewhere for explaining limiting neutron star periods could be large enough also for the present purpose.

4 pages, 1 figure; AandA Research Note

References in corpus (3)

• X-ray Properties of Black-Hole Binaries
• The ATNF Pulsar Catalogue
• Mountains on Neutron Stars: Accreted vs. Non-Accreted crusts

Cited by in corpus (8)

• On mass-constraints implied by the relativistic precession model of twin-peak quasi-periodic oscillations in Circinus X-1
• Mass-angular-momentum relations implied by models of twin peak quasi-periodic oscillations
• Black hole spin inferred from 3:2 epicyclic resonance model of high-frequency quasi-periodic oscillations
• Constraining models of twin peak quasi-periodic oscillations with realistic neutron star equations of state
• Confronting models for the high-frequency QPOs with Lense-Thirring precession
• Appearance of innermost stable circular orbits of accretion discs around rotating neutron stars
• Black Holes Admitting Strong Resonant Phenomena
• Of Mountains and Molehills : Gravitational Waves from Neutron Stars