Radio flare in M81
ATel #3621; Guy Pooley (MRAO, Cavendish Lab, Cambridge UK)
on 1 Sep 2011; 09:18 UT
Credential Certification: Guy Pooley (ggp1@cam.ac.uk)
The nucleus of the SA galaxy M81 has long been known as a variable radio source (Ho et al, AJ 118 843 (1999)). Recent observations with the AMI Large Array at MRAO, Cambridge (UK) at 15.75 GHz
have shown an unusually large outburst. The last three observations were:
2011 Aug 24.31 140 mJy;
2011 Aug 27.47 261 mJy;
2011 Sep 01.25 321 mJy.
Over the previous 5 years, the mean flux density was 116 mJy, with extremes of 53 and 210 mJy.
Further observations in other wavebands are encouraged.