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Flux Modulation from Non-Axisymmetric Stuctures in Accretion Discs

P. Varniere·E. Blackman
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Abstract

Non-axisymmetric accretion discs can lead to flux variability. Here we provide an analytic framework for modeling non-axisymmetric structures like hotspots and spiral waves and their influence on observed timing measurements. The presently unexplained Low-frequency Quasi-Periodic Oscillations (LFQPO), observed in X-ray binaries and cataclysmic variables, could be the result of such discs. Our framework serves as a guide to quantify the properties that non-axisymmetric structures produced by nonlinear accretion disc models must have in order to explain observed features such as LFQPOs. The results from our microquasar appliations also provide analogous predictions for X-ray modulation in active galactic nuclei. The formalism and physical interpration is of practical use for generic non-axisymmetric accretion disc systems.

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P. Varniere, E. Blackman. 2005-06-06. Flux Modulation from Non-Axisymmetric Stuctures in Accretion Discs. https://doi.org/10.1016/j.newast.2005.05.005

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