Outbursts of irradiated accretion discs |
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| Authors: | King |
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| Institution: | Astronomy Group, University of Leicester, Leicester LE1 7RH |
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| Abstract: | I solve analytically the viscous evolution of an irradiated accretion disc, as seen during outbursts of soft X-ray transients. The solutions predict steep power-law X-ray decays L X ∼ (1 + t/tvisc)−4, changing to L X ∼ (1 − t/t'visc)4 at late times, where t visc, t 'visc are viscous time-scales. These forms closely resemble the approximate exponential and linear decays inferred by King and Ritter in these two regimes. The decays are much steeper than for unirradiated discs because the viscosity is a function of the central accretion rate rather than of local conditions in the disc. |
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| Keywords: | accretion accretion discs instabilities X-rays: stars |
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