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arXiv · 0911.3804

Searching for flickering statistics in T CrB

A. Dobrotka·L. Hric·J. Casares·T. Shahbaz·I. G. Martinez-Pais·T. Munoz-Darias
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Abstract

We analyze $V$-band photometry of the aperiodic variability in T CrB. By applying a simple idea of angular momentum transport in the accretion disc, we have developed a method to simulate the statistical distribution of flare durations with the assumption that the aperiodic variability is produced by turbulent elements in the disc. Both cumulative histograms with Kolmogorov-Smirnov tests, and power density spectra are used to compare the observed data and simulations. The input parameters of the model $R_{\rm in}$ and $α$ are correlated on a certain interval and the most probable values are an inner disc radius of $R_{\rm in} \simeq 4 \times 10^9$ cm and a viscosity of $α\simeq 0.9$. The disc is then weakly truncated. We find that the majority of turbulent events producing flickering activity are concentrated in the inner parts of the accretion disc.

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A. Dobrotka, L. Hric, J. Casares, T. Shahbaz, I. G. Martinez-Pais, T. Munoz-Darias. 2009-11-19. Searching for flickering statistics in T CrB. https://doi.org/10.1111/j.1365-2966.2009.16068.x

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