Impulsive Brightening and Variability Timescales in the M87 Jet

D. E. Harris, SAO

D. E. Harris (SAO), C. C. Cheung (GSFC), L. Stawarz (KIPAC), and J. A. Biretta (STScI)

We have been monitoring the M87 jet with sub-arcsec resolution since 2002 in radio, optical, and X-rays. From an analysis of the first derivative of the X-ray lightcurve we find evidence for an unexpected oscillation in the brightening and fading of HST-1. This knot which lies 0.86" (60pc projected) from the nucleus, displayed a giant flare that peaked in 2005, coinciding with the maximum observed TeV intensity from M87. We evaluate various timescales to determine if differences in radio, optical, and X-rays can be attributed to loss mechanisms suffered by the relativistic electrons responsible for the observed emissions. The work at SAO was supported by NASA grants NAS GO6-7112X and GO7-8119X.