Nonradial pulsations of accretion disks: The nature of quasi-periodic oscillations in dwarf novae

Journal Article · Fri Feb 01 04:00:00 EST 1980 · Astrophys. J., Lett. Ed.; (United States)

DOI:https://doi.org/10.1086/183178· OSTI ID:5286447

Van Horn, H M; Wesemael, F; Winget, D E

Quasi-periodic oscillations on time scales from approx.30 s to approx.150 s, which have been observed in several dwarf novae during outburst, have been qualitatively interpreted as oscillations of the accretion disks in these systems. We investigate this suggestion quantitatively by showing that there exist nonradial oscillation modes of the disk that, being weakly coupled in the radial (omega-bar) direction, correspond to oscillations of individual disk annuli which are periodic in phi, z, and t. The frequencies of these oscillations are directly proportional to the rotation frequency of the annulus. Because the luminosity of an annulus is largest at some intermediate radius, the oscillations are expected to be most evident for annuli near this radius. For values of the parameters typical of dwarf novae, the corresponding oscillation periods are approx.20 s, with a range from approx.10 to approx.150 s. We suggest that these modes correspond to the observed quasi-periodic oscillations.

• Research Organization: Department of Physics and Astronomy, and C. E. Kenneth Mees Observatory, University of Rochester
• OSTI ID: 5286447
• Journal Information: Astrophys. J., Lett. Ed.; (United States), Journal Name: Astrophys. J., Lett. Ed.; (United States) Vol. 235:3; ISSN AJLEA
• Country of Publication: United States
• Language: English

Related Subjects

640102* -- Astrophysics & Cosmology-- Stars & Quasi-Stellar
Radio & X-Ray Sources
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ERUPTIVE VARIABLE STARS
NOVAE
OSCILLATIONS
PULSATING VARIABLE STARS
STAR ACCRETION
STAR EVOLUTION
STARS
VARIABLE STARS