{
  "bibcode": "2013GCN.14898....1E",
  "body": "J. Elliott (MPE Garching), S. Schmidl (TLS Tautenburg), J.Greiner\n(MPE Garching), D. A. Kann (TLS Tautenburg), S. Ciceri and L. Mancini\n(both MPIA) report on behalf of the GROND team:\n\nWe observed the field of GRB 130615A (Swift trigger 558271, Sonbas et al.,\nGCN #14897) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,\nPASP 120, 405) mounted at the 2.2 m MPG/ESO telescope at La Silla\nObservatory (Chile).\n\nObservations started on June 15, 2013, at 10:17:21 UT, 0.54 hrs after the\nGRB trigger. They were performed at an average seeing of 1\".1 and at an\naverage airmass of 1.9.\n\nWe find a source inside the enhanced 2\".1 SWIFT/XRT error circle\n(http://www.swift.ac.uk/sper/558271/) at\n\nRA (J2000.0) = 18:19:19.11\n\nDEC (J2000.0) = -68:09:40.5\n\nwith an uncertainty of 0\".5 in each coordinate.\n\nBased on a total exposure time of 263 s in g'r'i'z' and 240 s in JHK, at a\nmidtime of 0.82 hrs after the burst, we measure the following preliminary\nAB magnitudes:\n\ng' = 21.3 +/- 0.1 mag,\nr' = 20.7 +/- 0.1 mag,\ni' = 20.6 +/- 0.1 mag,\nz' = 20.5 +/- 0.1 mag,\nJ = 20.2 +/- 0.3 mag,\nH = 19.8 +/- 0.3 mag and\nK > 19.1 mag\n\nConsidering the galactic foreground extinction, the fit to the spectral\nenergy distribution indicates a redshift <~ 3.\n\nGiven magnitudes are calibrated against GROND zeropoints as well as\n2MASS field stars and are not corrected for the expected Galactic\nforeground extinction corresponding to a reddening of E_(B-V)=0.12 mag\nin the direction of the burst (Schlegel et al. 1998).",
  "circularId": 14898,
  "createdOn": 1371300277000,
  "email": "schmidl@tls-tautenburg.de",
  "subject": "GRB 130615A: GROND afterglow candidate",
  "submitter": "Sebastian Schmidl at TLS Tautenburg  <schmidl@tls-tautenburg.de>",
  "eventId": "GRB 130615A"
}