{
  "bibcode": "2016GCN.20169....1E",
  "body": "S. W. K Emery (MSSL-UCL) and A. D'Ai (INAF-IASFPA) report on behalf\nof the Swift/UVOT team:\n\nSwift-UVOT performed follow-up observations of the Fermi/LAT-detected\nburst GRB 161109A (Desiante et al. GCN Circ. 20155) in a series of\nobservations tiled on the sky. Observations were taken in the u band\nfilter between T0+40.4 ks and T0+63.3 ks after the Fermi trigger.\n\nSwift/UVOT did not find any new optical counterpart. The 3 sigma\nupper limits at the position of each of the uncatalogued X-ray sources (Gibson et\nal. GCN Circ. 20164) are:\n\nSource  T_start (s)  T_end (s)  Exposure Time (s)  filter   3s UL\n\nSource 2     40425     57980     1152     u     20.11\nSource 3     40425     57980     1152     u     20.08 \nSource 6     41245     63272     1121     u     19.22\n\nThe magnitudes in the table are not corrected for the Galactic\nextinction due to the reddening of E(B-V) = 0.01 in the direction of\nthe burst (Schlegel et al. 1998).",
  "circularId": 20169,
  "createdOn": 1478878475000,
  "email": "samuel.emery.15@ucl.ac.uk",
  "subject": "GRB 161109A: Swift/UVOT Upper Limits",
  "submitter": "Sam Emery at MSSL-UCL  <samuel.emery.15@ucl.ac.uk>",
  "eventId": "GRB 161109A"
}