{
  "bibcode": "2020GCN.28980....1P",
  "body": "M. Perri (ASDC), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), A. Tohuvavohu\n(U. Toronto), B. Sbarufatti (PSU), D.N. Burrows (PSU), J.P. Osborne (U.\nLeicester), K.L. Page (U. Leicester) and P.A. Evans (U. Leicester)\nreport on behalf of the Swift-XRT team:\n\nSwift-XRT has performed follow-up observations of the\nSwift/BAT-detected burst GRB 201128B (James DeLaunay et al. GCN Circ.\n28971), collecting 5.0 ks of Photon Counting (PC) mode data between\nT0+246.0 ks and T0+303.8 ks. \n\nTen uncatalogued X-ray sources have been detected, however none of them\nis above the RASS limit or shows definitive signs of fading. Therefore,\nat the present time we cannot identify which, if any, is the afterglow.\nDetails of these sources are given below:\n\nSource 1:\n  RA (J2000.0):  339.4164  =  22:37:39.94\n  Dec (J2000.0): -49.2698  =  -49:16:11.1\n  Error: 5.1 arcsec (radius, 90% conf.)\n  Count-rate: (3.32 [+1.13, -0.93])e-3 ct s^-1\t \n  Distance: 169 arcsec from Swift/BAT position.\n  Flux: (1.67 [+0.57, -0.47])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 2:\n  RA (J2000.0):  339.0250  =  22:36:5.99\n  Dec (J2000.0): -49.1319  =  -49:07:54.7\n  Error: 5.2 arcsec (radius, 90% conf.)\n  Count-rate: (4.7 [+2.8, -2.0])e-3 ct s^-1   \n  Distance: 876 arcsec from Swift/BAT position.\n\nSource 4:\n  RA (J2000.0):  339.5648  =  22:38:15.55\n  Dec (J2000.0): -49.2141  =  -49:12:50.9\n  Error: 7.7 arcsec (radius, 90% conf.)\n  Count-rate: (2.35 [+1.05, -0.81])e-3 ct s^-1\t \n  Distance: 508 arcsec from Swift/BAT position.\n  Flux: (7.8 [+3.5, -2.7])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 5:\n  RA (J2000.0):  339.4267  =  22:37:42.42\n  Dec (J2000.0): -49.1173  =  -49:07:02.2\n  Error: 5.3 arcsec (radius, 90% conf.)\n  Count-rate: (1.36 [+0.77, -0.57])e-3 ct s^-1\t \n  Distance: 494 arcsec from Swift/BAT position.\n  Flux: (9.5 [+5.4, -4.0])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 6:\n  RA (J2000.0):  339.2905  =  22:37:9.71\n  Dec (J2000.0): -49.3858  =  -49:23:08.7\n  Error: 5.1 arcsec (radius, 90% conf.)\n  Count-rate: (6.6 [+2.0, -1.6])e-3 ct s^-1   \n  Distance: 524 arcsec from Swift/BAT position.\n  Flux: (1.69 [+0.50, -0.42])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 7:\n  RA (J2000.0):  339.2768  =  22:37:6.43\n  Dec (J2000.0): -49.1392  =  -49:08:21.0\n  Error: 4.9 arcsec (radius, 90% conf.)\n  Count-rate: (4.7 +/- 1.3)e-3 ct s^-1\t \n  Distance: 425 arcsec from Swift/BAT position.\n  Flux: (2.03 +/- 0.55)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 8:\n  RA (J2000.0):  339.2888  =  22:37:9.31\n  Dec (J2000.0): -49.1961  =  -49:11:45.9\n  Error: 7.2 arcsec (radius, 90% conf.)\n  Count-rate: (2.17 [+0.97, -0.77])e-3 ct s^-1\t \n  Distance: 236 arcsec from Swift/BAT position.\n  Flux: (1.84 [+0.83, -0.65])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 9:\n  RA (J2000.0):  339.2747  =  22:37:5.92\n  Dec (J2000.0): -49.1221  =  -49:07:19.5\n  Error: 9.8 arcsec (radius, 90% conf. [Enhanced position])\n  Count-rate: (3.04 [+1.19, -0.95])e-3 ct s^-1\t \n  Distance: 483 arcsec from Swift/BAT position.\n  Flux: (7.4 [+2.9, -2.3])e-14 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 10:\n  RA (J2000.0):  339.5188  =  22:38:4.51\n  Dec (J2000.0): -49.1801  =  -49:10:48.4\n  Error: 6.9 arcsec (radius, 90% conf.)\n  Count-rate: (1.89 [+0.94, -0.72])e-3 ct s^-1\t \n  Distance: 454 arcsec from Swift/BAT position.\n  Flux: (3.0 [+1.5, -1.1])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nSource 11:\n  RA (J2000.0):  339.5043  =  22:38:1.04\n  Dec (J2000.0): -49.3084  =  -49:18:30.2\n  Error: 5.2 arcsec (radius, 90% conf.)\n  Count-rate: (2.14 [+1.07, -0.81])e-3 ct s^-1\t \n  Distance: 418 arcsec from Swift/BAT position.\n  Flux: (1.04 [+0.52, -0.39])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)\n\nA catalogued source was also detected.\n\nThe results of the XRT-team automatic analysis of the XRT observations,\nincluding a position-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/ToO_GRBs/00021044.\n\nThis circular is an official product of the Swift-XRT team.",
  "circularId": 28980,
  "createdOn": 1606921977000,
  "email": "antonino.dai@inaf.it",
  "subject": "GRB 201128B: Swift-XRT observations",
  "submitter": "Antonino D'Ai at IASF-PA  <antonino.dai@inaf.it>",
  "eventId": "GRB 201128B"
}