{
  "bibcode": "2017GCN.22060....1M",
  "body": "D. Malesani (DARK/NBI), N. R. Tanvir (Univ. Leicester), P. Schady (MPE), \nA. de Ugarte Postigo (IAA/CSIC and DARK/NBI), K. E. Heintz (Univ. \nIceland and DARK/NBI), G. Pugliese (API, Univ. Amsterdam), report on \nbehalf of the Stargate collaboration:\n\nWe observed the field of GRB 171027A (D'Avanzo et al., GCN 22053) with \nthe ESO Very Large Telescope (VLT) UT2 equipped with X-shooter. \nObservations started on 2017 Oct 27.379 UT (42.8 min after the trigger) \nusing the acquisition camera, entirely during twilight. For this reason, \nonly short exposures could be secured (45 s in r, 60 s in z).\n\nWithin the prompt-enhanced XRT position (Evans, GCN 22054) we find no \nnew sources down to r > 23, z > 22.7 mag (all AB, calibrated against the \nPan-STARRS catalog). Our results are consistent with the lack of optical \ndetection by GROND (Schady, GCNs 22056, 22058), RATIR (Watson et al., \nGCN 22057), and LCO (Guidorzi, GCN 22059). In particular, we confirm \nthat no object is visible at the position of the NIR candidate reported \nby Watson et al. (GCN 22057).\n\nWe acknowledge excellent support from the ESO staff, in particular \nMichael Hilker and Francisco Labrana.",
  "circularId": 22060,
  "createdOn": 1509105718000,
  "email": "malesani@dark-cosmology.dk",
  "subject": "GRB 171027A: VLT optical upper limits",
  "submitter": "Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani@dark-cosmology.dk>",
  "eventId": "GRB 171027A"
}