{
  "bibcode": "2015GCN.18698....1D",
  "body": "M. De Pasquale (UCL-MSSL) and S. L. Gibson (U Leicester)\nreport on behalf of the Swift/UVOT team:\n\nThe Swift/UVOT began settled observations of the field of GRB 151215A\n174 s after the BAT trigger (Gibson et al., GCN Circ. 18691).\nWe detect the optical afterglow of GRB151215A within the XRT error\ncircle (Evans et al. GCN Circ. 18695), in the initial UVOT exposures.\n\nThe preliminary UVOT position is:\n     RA  (J2000) =  06:14:20.25 =  93.58438 (deg.)\n     Dec (J2000) = +35:30:57.4  =  35.51595 (deg.)\nwith an estimated uncertainty of 0.46 arc sec. (radius, 90% confidence).\n\nThe position of this source is consistent with those given by Cenko et al.\n(GCN Circ. 18692) and GROND (Wiseman et al. GCN Circ. 18694).\n\nThere is no detection in UVOT uv filters, which is congruous with\nthe redshift z=2.6 of the event (Xu et al., GCN circ. 18696).\n\nPreliminary detections and 3-sigma upper limits using the UVOT \nphotometric system\n(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early \nexposures are:\n\nFilter                     T_start(s)   T_stop(s) Exp(s)           Mag\n\nwhite (Finding Chart)         174          323          147 19.05 �� 0.14\nwhite                         531         2586          362 20.59 �� 0.19\nv                             408         2636          253 19.67 �� 0.35\nb                             507         2561          233 20.85 �� 0.42\nu                             482         2536          233 >20.3\nw1                            458         2512          233 >19.9\nm2                            433         2651          225 >19.6\nw2                            384         2612          253 >19.9\n\nThe magnitudes in the table are not corrected for the substantial Galactic\nextinction due to the reddening of E(B-V) = 0.39 in the direction of the \nburst\n(Schlegel et al. 1998).\n\n-- \n\nDr. Massimiliano De Pasquale\nResearch associate - Swift UVOT scientist\nMullard Space Science Laboratory, University College London",
  "circularId": 18698,
  "createdOn": 1450196913000,
  "email": "m.depasquale@ucl.ac.uk",
  "subject": "GRB151215A: Swift/UVOT detection",
  "submitter": "Massimiliano de Pasquale at IASF-Palermo  <m.depasquale@ucl.ac.uk>",
  "eventId": "GRB 151215A"
}