GRB 070724B: The first Gamma Ray Burst Localized by SuperAGILE and its Swift X-ray Afterglow

GRB 070724B is the first gamma ray burst localized by SuperAGI LE, the hard X-ray monitor aboard the AGILE satellite. The coordinates of the event were published∼ 19 hours after the trigger. The Swift X-Ray Telescope pointed at the SuperAGILE location and detected the X-ray afterglow inside the SuperAGILE error circle. The AGILE gamma-ray Tracker and Minicalorimeter did not detect any significant gamma ray emission associated with GR B 070724B in the MeV and GeV range, neither prompt nor delayed. Searches for the optical afterglow were performed by the Swift UVOT and the Palomar automated 60-inch telescopes, resulting in no significant detection. Similarly, the Very Large Array did n ot detect any radio afterglow. This is the first GRB event asso ciated with an X-ray afterglow with a firm upper limit in the 100 MeV ‐ 30 GeV energy range.