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arXiv · 1501.02628

Optical Flickering of the recurrent nova RS Ophiuchi: amplitude - flux relation

R. Zamanov·G. Latev·S. Boeva·J. L. Sokoloski·K. Stoyanov·R. Bachev·B. Spassov·G. Nikolov·V. Golev·S. Ibryamov
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Abstract

We report observations of the flickering variability of the symbiotic recurrent nova RS~Oph at quiescence in five bands ($UBVRI$). We find evidence of a correlation between the peak-to-peak flickering amplitude ($ΔF$) and the average flux of the hot component ($F_{\rm av}$). The correlation is highly significant, with a correlation coefficient of 0.85 and a $p$-value of~$\sim 10^{-20}$. Combining the data from all wavebands, we find a dependence of the type $ΔF \propto F^k_{\rm av}$, with power-law index $k = 1.02 \pm 0.04$ for the $UBVRI$ flickering of RS~Oph. Thus, the relationship between the amplitude of variability and the average flux of the hot component is consistent with linearity. The rms amplitude of flickering is on average 8 per cent ($\pm2$ per cent) of $F_{\rm av}$. The detected correlation is similar to that found in accreting black holes/neutron stars and cataclysmic variables. The possible reasons are briefly discussed. The data are available upon request from the authors.

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R. Zamanov, G. Latev, S. Boeva, J. L. Sokoloski, K. Stoyanov, R. Bachev, B. Spassov, G. Nikolov, V. Golev, S. Ibryamov. 2015-05-21. Optical Flickering of the recurrent nova RS Ophiuchi: amplitude - flux relation. https://doi.org/10.1093/mnras%2Fstv873

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