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UBVRI observations of the flickering of the dwarf nova RX And

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 نشر من قبل Radoslav K. Zamanov
 تاريخ النشر 2021
  مجال البحث فيزياء
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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 $Bapprox 13.9$ mag, the amplitude of the flickering was 0.47 mag, and we estimate for the flickering source temperature $T_{fl} = 10700 pm 400$ K, and radius $R_{fl} =0.046 pm 0.004$ $R_odot$. On 2 January 2020, the star was about 3 magnitudes brighter ($B approx 10.7$), the amplitude of the flickering was significantly lower (0.07 mag) and we derive for the flickering source $T_{fl} = 9600 pm 700$ K, and radius $R_{fl} = 0.098 pm 0.009$ $R_odot$. 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.



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