{
  "bibcode": "2014GCN.16304....1T",
  "body": "A. Trotter, A. LaCluyze, J. Haislip, D. Reichart, K. McLin, L. Cominsky, \nH. T. Cromartie, A. Foster, N. Frank, K. Ivarsen, M. Maples, J. Moore, \nM. Nysewander, R. Beauchemin, T. Berger, A. Dow, M. Hinckle, A. \nPatterson, H. Pegues, J. Pozo, D. Waddell, and J. A. Crain report:\n\nSkynet observed the Swift-XRT localization of GRB 140518A (Melandri et \nal., GCN 16298, Swift trigger 599287) with the 14\" GLAST Optical Robotic \nTelescope (GORT) at the Hume observatory in CA, USA. Observations began \nat t=130s and continued until 2.4h post-trigger. Skynet took alternating \nexposures in the Rc and Ic bands, increasing from 10s to 160s. In early \nIc and Rc images, and in later stacked Ic images, we detect an \nuncatalogued fading optical source at a position consistent with the \nafterglow candidate reported by Zheng et al. (GCN 16299).\n\nThe source faded from Ic=16.8 at t=130s to Ic > 18.7 at a mean time \nt~70m. In Rc band, we detect the source marginally at Rc~18.3 at t=4m, \nwith Rc>20.1 at a mean time t~55m.\n\nA preliminary light curve is at:\nhttp://www.skynet.unc.edu/grb/grb140518a.png\n\nPhotometry is calibrated to six APASS-DR7 stars in the field, and has \nnot been corrected for the Galactic foreground extinction corresponding \nto E(B-V)=0.016 (Schlegel et al. 1998).\n\nNo further Skynet observations are scheduled.",
  "circularId": 16304,
  "createdOn": 1400437481000,
  "email": "atrotter@physics.unc.edu",
  "subject": "GRB 140518A: Skynet GORT Detections of the Optical Afterglow",
  "submitter": "Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet  <atrotter@physics.unc.edu>",
  "eventId": "GRB 140518A"
}