The Anomalous Early Afterglow of GRB 050801
  The ROTSE-IIIc telescope at the H.E.S.S. site, Namibia, obtained the earliest detection of optical emission from a Gamma-Ray Burst (GRB), beginning only 21.8 s from the onset of Swift GRB 050801. The optical lightcurve does not fade or brighten significantly over the first ~250 s, after which there is an achromatic break and the lightcurve declines in typical power-law fashion. The Swift/XRT also obtained early observations starting at 69 s after the burst onset. The X-ray lightcurve shows the same features as the optical lightcurve. These correlated variations in the early optical and X-ray emission imply a common origin in space and time. This behavior is difficult to reconcile with the standard models of early afterglow emission. 
E. S. Rykoff, V. Mangano, S. A. Yost, R. Sari, F. Aharonian, C. W.   Akerlof, M. C. B. Ashley, S. D. Barthelmy, D. N. Burrow...