{
  "bibcode": "2005GCN..3521....1B",
  "body": "D. Bersier, A. Fruchter, J. Rhoads, (STScI), A. Levan (U. of\nLeicester), N. Tanvir (Hertsfordshire) report on behalf of a larger\ncollaboration:\n\nWe have observed the field of GRB 050509b (Hurkett et al,\nGCN 3379) with the Gemini Multi-Object Spectrograph on the\nGemini-North telescope.  We obtained imaging data (Sloan filters)\non May 13, May 17 and May 28.\n\nPSF-matched image subtraction of the May 13 and May 17 data from \nthe May 28 image reveals no variable sources down to 26.5 on May 14\nand 26.4 on May 17 (3-sigma limits).  At the redshift of the\ncluster this would imply that any unextincted SN would be\nmore than 4 magnitude fainter than SN 1998bw.\nFurthermore, our detection limit on May 28 is ~27.4. At that epoch,\na supernova like SN 1998bw would be 6 mag brighter than this.\nThere is no such bright source in the XRT error circle.",
  "circularId": 3521,
  "createdOn": 1118029540000,
  "email": "bersier@stsci.edu",
  "subject": "Limits on a SN in the field of GRB 050509b",
  "submitter": "David Bersier at STScI  <bersier@stsci.edu>",
  "eventId": "GRB 050509B"
}