1ES 1218+304 detected in bright optical state with ATOM
ATel #13695; Felix Jankowsky, Stefan Wagner (Landessternwarte Heidelberg)
on 1 May 2020; 14:20 UT
Credential Certification: Felix Jankowsky (f.jankowsky@lsw.uni-heidelberg.de)
Subjects: Optical, AGN, Blazar, Transient
Optical observations of the BL Lac object 1ES 1218+304 with the Automatic Telescope for Optical Monitoring (ATOM) in Namibia show this blazar in a bright flare which appears to exceed previously reported levels. Preliminary analysis of measurements performed on 29 April, 2020 (MJD 58968.87) show an R magnitude of 15.0. The source flux has increased since the beginning of 2020 and exceeded the level of R band brightness of earlier flares detected in January and May/June 2011 and in January 2019, respectively, since 27 April, 2020.
1ES 1218+304 is a redshift 0.183 (Ahn et al., Astrophys. J. Suppl., 203, 21 (2012) BL Lac object, that has been reported to display significant variations in the very high energy band, with the previous optical flare being accompanied by high gamma-ray flux level (ATel #12360, #12354)
Further multifrequency observations of this outburst are encouraged.