A synchrotron self-Compton -- disk reprocessing model for optical/X-ray correlation in black hole X-ray binaries

Abstract

Physical picture of the emission mechanisms operating in the X-ray binaries was put under question by the simultaneous optical/X-ray observations with high time resolution. The light curves of the two energy bands appeared to be connected and the cross-correlation functions observed in three black hole binaries exhibited a complicated shape. They show a dip of the optical emission a few seconds before the X-ray peak and the optical flare just after the X-ray peak. This behavior could not be explained in terms of standard optical emission candidates (e.g., emission from the cold accretion disk or a jet). We propose a novel model, which explains the broadband optical to the X-ray spectra and the variability properties. We suggest that the optical emission consists of two components: synchrotron radiation from the non-thermal electrons in the hot accretion flow and the emission produced by reprocessing of the X-rays in the outer part of the accretion disk. The first component is anti-correlated with the X-rays, while the second one is correlated, but delayed and smeared relative to the X-rays. The interplay of the components explains the complex shape of the cross-correlation function, the features in the optical power spectral density as well as the time lags.

5 pages, 3 figures, ApJ Letters in press

References in corpus (11)

• Reprocessing of X-rays in the outer accretion disc of the black hole binary XTE J1817--330
• Rapid optical and X-ray timing observations of GX 339-4: multi-component optical variability in the low/hard state
• The synchrotron boiler and the spectral states of black hole binaries
• On the origin of spectral states in accreting black holes
• Rapid optical and X-ray timing observations of GX 339-4: flux correlations at the onset of a low/hard state
• A self-consistent hybrid Comptonization model for broad-band spectra of accreting supermassive black holes
• Evolution of the 0.01 - 25 Hz power spectral components in Cygnus X-1
• SWIFT J1753.5-0127: a surprising optical/X-ray cross-correlation function
• Multiwavelength spectral and high time resolution observations of SWIFT J1753.5-0127: new activity?
• High time resolution optical/X-ray cross-correlations for X-ray binaries: anti-correlations and rapid variability
• Electron thermalization and photon emission from magnetized compact sources

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