{
  "bibcode": "2016GCN.18936....1G",
  "body": "J. F. Graham, T. Schweyer, and J. Greiner (all MPE Garching) report on behalf of the GROND team:\n\nWe observed the field of GRB 160123A (Swift trigger 671447; Malesani, et al., GCN # 18926) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).\n\nObservations started at  04:02 UT on 25 Jan 2016, approximately 43 hours after the GRB trigger, and lasted for 2 hours. They were performed at an average seeing of 1.64\" and at an average airmass of 1.06.\n\nWe do not detect a source within the Swift-XRT error circle reported by Beardmore et al. (GCN # 18927) down to (AB magnitudes)\n\ng' > 24.1 mag,\nr' > 24.4 mag,\ni' > 24.0 mag,\nz' > 23.9 mag,\nJ > 21.3 mag,\nH > 20.9 mag, and\nK > 20.1 mag.\n\nThe given limits are derived based on calibrating the images against GROND zeropoints and 2MASS field stars and are not corrected for the Galactic foreground extinction corresponding to a reddening of E_(B-V)= 0.10 in the direction of the burst (Schlegel et al. 1998).",
  "circularId": 18936,
  "createdOn": 1453812615000,
  "email": "graham@mpe.mpg.de",
  "subject": "GRB 160123A: GROND Upper limits",
  "submitter": "John Graham at MPE/Garching  <graham@mpe.mpg.de>",
  "eventId": "GRB 160123A"
}