OAUNI confirmation of optical flickering from RS Oph

Abstract

We report photometry post 2021 outburst of the recurrent nova RS Oph on 2022-05-02 (UT) gathered with the OAUNI 51cm telescope (Pereyra et al. 2015; arXiv:1512.03104) at Huancayo Observatory, Peru. CCD imaging was performed in B filter under non-photometric conditions (seeing ~1.8") and airmass ~1.1. The observations span 1.7h with a total of 220 individual measurements of 20s each. UCAC4 field stars (417-071319 and 418-073342) were used for the zero point calibration. An average B magnitude of 12.43 +/- 0.04 (HJD middle = 2459701.772) is found with a clear detection of optical flickering on minute-to-hour time scale with peak-to-peak amplitude of 0.22 mag (see link below). This is supported by the standard deviation ratio of magnitudes between RS Oph and the comparison stars that is 2.8. Our observations confirm previous RS Oph optical flickering detections post last outburst (ATel #15330, ATel #15339). Following the onset of the 2021 outburst (Munari & Valisa 2021; arXiv:2109.01101), our measurements are 266.8 days old with an ongoing re-establishment of accretion. The OAUNI project is supported by UNI, TWAS, IGP and ProCiencia-Concytec (Convenio 133-2020 Fondecyt).