UBVRI observations of the flickering of the dwarf nova RX And

Abstract

We report observations of the flickering variability of the dwarf nova RX And in five bands (UBVRI) on two nights. On 25 October 2019 the brightness of the star was B≈ 13.8 mag, the amplitude of the flickering was 0.47 mag, and we estimate for the flickering source temperature T_fl = 10700 ± 400 K, and radius R_fl =0.046 ± 0.004 R_⊙. On 2 January 2020, the star was about 3 magnitudes brighter (B ≈ 10.7), the amplitude of the flickering was significantly lower (0.07 mag) and we derive for the flickering source T_fl = 9600 ± 700 K, and radius R_fl = 0.098 ± 0.008 R_⊙. The results indicate that 3 magnitudes brightening of the star doubled the radius of the flickering source.

The data are available upon request from the authors.