Difference between the optical flickering colours of cataclysmic variables and symbiotic recurrent novae

Institute of Astronomy and National Astronomical Observatory, Bulgarian Academy of Sciences, 72 Tsarigradsko shose,BG-1784, Sofia, BulgariaReceived 2 September 2014, accepted 2014 Dec 04Published online 2015 Mar 01Key words Stars: binaries – novae, cataclysmic variables – binaries: symbiotic – stars: individual: T CrB, RS OphWe performed simultaneous observations in 3 bands (UBV)of the flickering variability of the recurrent novae RS Ophand T CrB at quiescence. Using new and published data, we compare the colours of the flickering in cataclysmic variablesand symbiotic recurrent novae. We find a difference between t he colours of the flickering source in these two types ofaccreting white dwarfs. The detected difference is highly significant with p−value≈2×10