R. Bachev (IA-NAO, BAS, Bulgaria) reported in ATEL #15447 that blazar (flat spectrum radio quasar, FSRQ) AU CVN = B2 1308+326 is in outburst and reached "...R = 14.4 (T. Balonek, priv.comm.) on 2022-06-19, which was probably the highest reported optical level for the last 40 years." My observations on 25 June and on 26 June show its brightness is still increasing. The following Ic mean magnitudes were obtained at Burleith Observatory, Washington, DC (0.32-m PlaneWave CDK, STL1001e CCD, Astrodon Cousins I filter, 180-sec exposures). Ensemble photometry using (Smith, et al., AJ, 90, 1184,1985) comparisons A,B,C,F.
Mean UT Mean HJD Mean Ic standard error Number of observations
June 25.1046 2022 2459755.604572 12.860 (0.002) 39
June 26.1027 2022 2459756.602745 12.720 (0.003) 36
R. Schmidt (SREB)
AU CVn is still on the rise tonight. The following Ic mean magnitudes were obtained at Burleith Observatory, Washington, DC (0.32-m PlaneWave CDK, STL1001e CCD, Astrodon Cousins I filter, 180-sec exposures). Ensemble photometry using (Smith, et al., AJ, 90, 1184,1985) comparisons A,B,C, check star F.
Mean UT Mean HJD Mean Ic standard error Number of observations
June 28.1021 2022. 2459758.602146 12.341 (0.001). 25
Rich Schmidt (SREB)