2005/02/28 by C. M. Zhang, H. X. Yin, Y. H. Zhao
Physics and Astronomy · #astro-ph
paper · pdf · doi:10.1086/518129
published as Publ.Astron.Soc.Pac.119:393-397,2007 · 11 pages, 1 figure, accepted by PASP
arxiv created 2007/03/14 · arxiv updated 2009/12/01
It is found that there exists an empirical linear relation between the high frequency \nhigh and low frequency \nlow of quasi-periodic oscillations (QPOs) for black hole candidate (BHC), neutron star (NS) and white dwarf (WD) in the binary systems, which spans five orders of magnitude in frequency. For the NS Z (Atoll) sources, νhigh and νlow are identified as the lower kHz QPO frequency and horizontal branch oscillations (HBOs) \nh (broad noise components); for the black hole candidates and low-luminosity neutron stars, they are the QPOs and broad noise components at frequencies between 1 and 10 Hz; for WDs, they are the ``dwarf nova oscillations'' (DNOs) and QPOs of cataclysmic variables (CVs). To interpret this relation, our model ascribes νhigh to the Alfvén wave oscillation frequency at a preferred radius and νlow to the same mechanism at another radius. Then, we can obtain \nlow = 0.08 \nhigh and the relation between the upper kHz QPO frequency \nt and HBO to be \nh ≃ 56 (\rm Hz) (\nt/\rm kHz)2, which are in accordance with the observed empirical relations. Furthermore, some implications of model are discussed, including why QPO frequencies of white dwarfs and neutron stars span five orders of magnitude in frequency.