{
  "bibcode": "2018GCN.22711....1D",
  "body": "A. de Ugarte Postigo (HETH/IAA-CSIC, Dark/NBI), L. Izzo, D. A. Kann \n(both HETH/IAA-CSIC), and A. Sota (IAA/CSIC) report on behalf of HETH:\n\nWe observed the field of GRB 180512A  (Deich et al.; GCN Circ. 22710) \nwith the 1.5-m OSN telescope in Granada, Spain\n\nObservations started at 22:15:35 UT (827 s after the GRB trigger) for \nOSN, and we obtained 8x60s images in the Rc band and 6x300s images in \nthe Ic band. Observations were obtained in inclement conditions (bad \nseeing of ~3\").\n\nIn our stacked images, we find no source inside the Swift-XRT error \ncircle down to a 3-sigma limit of Ic (Vega) > 21. The calibration was \nperformed using nearby stars in the SDSS catalog.",
  "circularId": 22711,
  "createdOn": 1526168231000,
  "email": "kann@iaa.es",
  "subject": "GRB 180512A: Upper limits from OSN",
  "submitter": "Alexander Kann at IAA-CSIC  <kann@iaa.es>",
  "eventId": "GRB 180512A"
}