{
  "bibcode": "2010GCN.10684....1G",
  "body": "P. Goldoni (APC/Univ. Paris 7 and SAp/CEA), H. Flores (Paris Obs.), D. \nMalesani (DARK/NBI), A. J. Levan (Univ. Warwick), N. R. Tanvir (Univ. \nLeicester), J. P. U. Fynbo (DARK/NBI), report on behalf of a larger \ncollaboration:\n\nWe observed the optical afterglow of GRB 100425A (Grupe et al., GCN \n10673; Malesani et al., GCN 10680; Olivares et al., GCN 10683) with th \nESO VLT equipped with the X-shooter spectrograph. Four spectra lasting \n10 minutes each were obtained, covering the spectral range 3000-25000 \nAA, starting on 2010 April 25, at 6:53 UT (4.0 hr after the GRB).\n\nWe detect the traces of both objects lying within the XRT error circle. \nPreliminary inspection of the spectrum of the afterglow reveals several \nabsorption features which we interpret as due to Mg II and Fe II, at a \ncommon redshift z = 1.755.\n\nWe caution that the data reduction was carried out using archival \ncalibration files. We acknowledge a particularly helpful and attentive \nsupport from the ESO staff in Paranal, especially Jonathan Smoker, \nLorena Faundez, Manuel Olivares and Steffen Mieske.",
  "circularId": 10684,
  "createdOn": 1272198455000,
  "email": "malesani@dark-cosmology.dk",
  "subject": "GRB 100425A: VLT/X-shooter redshift",
  "submitter": "Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>",
  "eventId": "GRB 100425A"
}