{
  "bibcode": "2020GCN.26989....1M",
  "body": "D. B. Malesani (DTU Space), L. Izzo (DARK/NBI), J. Palmerio (GEPI - \nParis Observatory), N. R. Tanvir (Univ. Leicester), A. J. Levan (Radboud \nUniv.), D. A. Kann (HETH-IAA/CSIC), report on behalf of the Stargate \nconsortium:\n\nWe observed the optical counterpart of GRB 200205A / Swift trigger \n954304 (Evans et al., GCN 26982), with the ESO VLT UT2 (Kueyen) equipped \nwith the X-shooter instrument. Unfortunately, observations could be \nstarted only late in twilight and no spectroscopy was secured.\n\nWe confirm the presence of an optical counterpart just outside the \ncurrently available (unenhanced) XRT position (Evans et al., GCN 26982; \nLipunov et al., GCN 26984; Melandri et al., GCN 26986). Its coordinates \nare (calibrated to the Gaia catalog; 0.2\" uncertainty):\n\nRA = 08:40:40.94\nDec = -35:16:25.1\n\nIn a 60-s image taken in the SDSS r filter at a mid time Feb 5.385 UT \n(2.63 hr after the BAT trigger), we measure for it r = 17.7+-0.1 AB, \nwhere the error is dominated by the scatter of the calibrators, chosen \nfrom the SkyMapper catalog (Wolf et al. 2018, PASA, 35, 010; \nhttps:doi.org/10.4225/41/593620ad5b574).\n\nWe note that the MAXI detection for a prolonged time at X-ray energies \n(Niwano et al., GCN 26987), the unusually large optical/gamma-ray \nbrightness ratio, and the low Galactic latitude (4 deg above the plane) \nmay indicate that this source is not a GRB but a Galactic transient. \nFurther analysis of the high-energy data, or ground-based spectroscopic \nobservations, will be necessary to distinguish among these options.\n\nWe acknowledge support from the ESO observing staff in Paranal, in \nparticular Elyar Sedaghati, Eleonora Sani, and Ditte Slumstrup.",
  "circularId": 26989,
  "createdOn": 1580927530000,
  "email": "malesani@space.dtu.dk",
  "subject": "GRB 200205A / Swift trigger 954304: VLT optical observations",
  "submitter": "Daniele B Malesani at DTU Space  <malesani@space.dtu.dk>",
  "eventId": "GRB 200205A"
}