{
  "bibcode": "2017GCN.22235....1B",
  "body": "D.N. Burrows (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.\nLeicester), A.P. Beardmore (U. Leicester), V. D'Elia (ASDC), A. D'Ai\n(INAF-IASFPA), A. Melandri (INAF-OAB), A. Tohuvavohu (PSU), S. J.\nLaPorte (PSU), P.A. Evans (U. Leicester), P. D'Avanzo (INAF-OAB) and \nN. P. M. Kuin (UCL-MSSL) report on behalf of the Swift team:\n\nSwift-XRT has performed follow-up observations of the\nFermi/LAT-detected burst GRB 171210A (Bissaldi et al. GCN Circ. 22228),\n\ncollecting 5.0 ks of Photon Counting (PC) mode data between T0+34.7 ks\nand T0+46.3 ks. \n\nFive uncatalogued X-ray sources have been detected, however none of\nthem is above the RASS limit or shows definitive signs of fading.\nTherefore, at the present time we cannot identify which, if any, is the\n\nafterglow. Details of these sources are given below:\n\nSource 1:\n  RA (J2000.0):  335.26545  =  22:21:3.71\n  Dec (J2000.0): +24.47028  =  +24:28:13.0\n  Error: 2.9 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: (7.5 [+1.5, -1.4])e-3 ct s^-1   \n  Distance: 182 arcsec from Fermi/LAT position.\n  Flux: (2.20 [+0.45, -0.41])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThis source lies 5.0\" away from SDSS J222103.88+242817.4, which is\ncatalogued as a candidate quasar (Brescia et al., 2015, MNRAS, 450,\n3893).\n\nSource 2:\n  RA (J2000.0):  335.2458  =  22:20:58.99\n  Dec (J2000.0): +24.6016  =  +24:36:05.7\n  Error: 5.7 arcsec (radius, 90% conf.)\n  Count-rate: (2.23 [+0.98, -0.76])e-3 ct s^-1\t \n  Distance: 618 arcsec from Fermi/LAT position.\n  Flux: (2.44 [+1.07, -0.83])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThis source lies 6.4\" away from SDSS J222058.65+243610.1, which is\ncatalogued as a candidate quasar (Brescia et al., 2015, MNRAS, 450,\n3893).\n\nSource 3:\n  RA (J2000.0):  335.4135  =  22:21:39.23\n  Dec (J2000.0): +24.5534  =  +24:33:12.4\n  Error: 7.0 arcsec (radius, 90% conf.)\n  Count-rate: (3.01 [+1.11, -0.90])e-3 ct s^-1\t \n  Distance: 530 arcsec from Fermi/LAT position.\n  Flux: (8.4 [+3.1, -2.5])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\nThis source lies 2.6\" away from SDSS J222139.19+243314.9, which is\ncatalogued as a candidate quasar (Brescia et al., 2015, MNRAS, 450,\n3893).\n\nSource 4:\n  RA (J2000.0):  335.42877  =  22:21:42.90\n  Dec (J2000.0): +24.30996  =  +24:18:35.9\n  Error: 2.4 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: 0.0137 +/- 0.0022 ct s^-1   \n  Distance: 608 arcsec from Fermi/LAT position.\n  Flux: (4.08 [+0.66, -0.64])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThis source lies 1.3\" away from SDSS J222142.87+241837.0, which is\ncatalogued as a candidate quasar (Brescia et al., 2015, MNRAS, 450,\n3893).\n\nSource 5:\n  RA (J2000.0):  335.37378  =  22:21:29.71\n  Dec (J2000.0): +24.49242  =  +24:29:32.7\n  Error: 2.3 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: (8.8 [+1.9, -1.8])e-3 ct s^-1   \n  Distance: 281 arcsec from Fermi/LAT position.\n  Flux: (3.00 [+0.65, -0.63])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nThis source lies 1.7\" away from SDSS J222129.58+242933.1, which is\ncatalogued as a candidate quasar (Brescia et al., 2015, MNRAS, 450,\n3893).\n\n\nThe results of the XRT-team automatic analysis of the XRT observations,\n\nincluding a position-specific upper limit calculator, are available at\nhttp://www.swift.ac.uk/ToO_GRBs/00020785.\n\n\nSimultaneous with the XRT, the UVOT observed the target region of GRB\n171210A. Due to the smaller field of view, two of the candidate sources\n(#2 and #4) are not on the UVOT image. The other candidate regions have\nbeen examined but do not show any new sources. A further comparison of\nthe whole UVOT observation to the DSS survey shows no new sources. \n\nWe acknowledge the use of the VizieR catalogue access tool, CDS,\nStrasbourg, France.\n\n\nThis circular is an official product of the Swift team.",
  "circularId": 22235,
  "createdOn": 1512998568000,
  "email": "paolo.davanzo@brera.inaf.it",
  "subject": "GRB 171210A: Swift-XRT and UVOT observations",
  "submitter": "Paolo D'Avanzo at INAF-OAB  <paolo.davanzo@brera.inaf.it>",
  "eventId": "GRB 171210A"
}