{
  "bibcode": "2012GCN.13649....1M",
  "body": "D. Malesani (DARK/NBI), S. Schulze (PUC and MCSS), A. de Ugarte Postigo \n(IAA/CSIC and DARK/NBI), D. Xu (WIS), V. D'Elia (INAF/Roma and \nASI/ASDC), J. P. U. Fynbo (DARK/NBI), N. R. Tanvir (Univ. Leicester), \nreport on behalf of a larger collaboration:\n\nWe observed the field of GRB 120815A (Pagani et al., GCN 13645) with the \nVLT/X-shooter spectrograph. We confirm the presence of a bright, \nuncatalogued object consistent with the GROND position (Sudilovsky et \nal., GCN 13648). From the acquisition images, we measure R = 18.9 for \nthe afterglow at an epoch of 1.67 hr after the GRB (calibrated to nearby \nUSNO stars).\n\nOur spectra cover the wavelength range 3000-25000 AA, and were taken \nstarting on 2012 Aug 15.163 UT (1.69 hr after the GRB), for a total of \n40 min exposure. Continuum from the afterglow is detected with high S/N \nin all of the UVB, VIS, and NIR arms.\n\nThe spectrum shows a wide trough and a multitude of strong absorption \nlines, which we interpret as due to a DLA and metal transitions of N V, \nS II, Si II, O I, C IV, Si IV, Fe II, Al II, Al III, Mn II, Mg II, Mg I, \namong others, at a common redshift z = 2.358. At the same redshift, we \nalso detect fine-structure lines of Ni II and Fe II, thus confirming \nconclusively that this is the GRB redshift. We also detect intervening \nsystems at z = 1.539, 1.693, and 2.00. In particular, the system at z = \n1.539 displays exceptionally strong Mg II, Mg I, and Fe II absorption.\n\nWe acknowledge the expert support of the VLT observing staff at Paranal, \nin particular Maja Vuckovic, Marcelo Lopez, and Thomas Rivinius.\nWe also thank Alex Kann for discussion on the afterglow identification.\n\n[GCN OPS NOTE(15aug12): Per author's request, ML and TR were added to the\nlast paragraph.]",
  "circularId": 13649,
  "createdOn": 1345009211000,
  "email": "malesani@dark-cosmology.dk",
  "subject": "GRB 120815A: VLT/X-shooter redshift",
  "submitter": "Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>",
  "eventId": "GRB 120815A"
}