{
  "eventId": "sb25081602",
  "submitter": "Phil Evans at U of Leicester <pae9@star.le.ac.uk>",
  "body": "P.A. Evans (U. Leicester), J.A. Kennea (PSU), E. Ambrosi  (INAF-IASFPA) , A.P.\nBeardmore (U. Leicester), M.G. Bernardini (INAF-OAB), R. Brivio (INAF-OAB), D.N.\nBurrows (PSU), S. Campana (INAF-OAB), M. Capalbi (INAF-OAR), A. D'Ai (INAF-IASFPA),\nP. D'Avanzo (INAF-OAB), V. D'Elia (SSDC & INAF-OAR), S. Dichiara (PSU), M. Ferro\n(INAF-OAB), A. Melandri (INAF-OAR), J.P. Osborne (U. Leicester), K.L. Page (U.\nLeicester), M. Perri (SSDC & INAF-OAR), C. Salvaggio (INAF-OAB), T. Sbarrato\n(INAF-OAB), B. Sbarufatti (INAF-OAB), M.A. Williams (PSU) report on behalf of the\nSwift-XRT team:\n\nSwift-XRT has performed follow-up observations of the SVOM/ECLAIRs-detected source\nsb25081602, collecting 1.7 ks of Photon Counting (PC) mode data between T0+1.8 ks\nand T0+7.3 ks after the trigger. We have detected 2 sources.  These have been\nautomatically classified as follows:\n  * 0 likely counterparts\n  * 0 candidate counterparts\n  * 0 uncatalogued X-ray sources\n  * 2 known X-ray sources\n\nKnown X-ray sources\n-------------------\n\n  Source 1 (SWIFT J051406.2-400234):\n  ==================================\n    RA (J2000.0):   78.5261  =\t05h 14m 06.26s\n    Dec (J2000.0):  -40.0430  =  -40d 02' 34.8\"\n    Error:\t    3.5 (arcsec, radius, 90% confidence).\n    Detect flag:    GOOD\n    Distance:\t    3.7 arcmin from the SVOM/ECLAIRs position.\n    Mean rate:\t    3.58 +/- 0.14 ct s^-1\n    Mean flux:\t    (1.474 +/- 0.058)e-10 erg cm^-2 s^-1\n    Peak rate:\t    6.7 +/- 1.5 ct s^-1\n    Peak flux:\t    (2.75 +/- 0.62)e-10 erg cm^-2 s^-1\n    ECF:\t    4.11e-11 erg cm^-2 ct^-1\n\t\t      assuming NH=9.61e+20 cm^-2, gamma=1.65\n\t\t      determined from a spectral fit.\n    This matches a catalogued X-ray source LSXPS J051406.5-400237\n    in the LSXPS catalogue. Details:\n    Separation:     4.4\" from the XRT source\n    Cat Rate:\t    5.0e+00 +/- 2.1e-02 ct s^-1 \n    Cat Flux:\t    2.1e-10 +/- 8.6e-13 erg cm^-2 s^-1 (0.3-10 keV)\n\t\t      so the source  is 1.1-sigma above the catalogued flux.\n    There is no evidence for fading.\n    This is 3.05\" from the SIMBAD position of 4U 0513-40, noted by  \n      Magnani et al. (GCN Circ. 41399).\n    There are 10 2MASS objects within the source's 3-sigma error radius.\n\n  Source 2 (SWIFT J051413.9-395933):\n  ==================================\n    RA (J2000.0):   78.5583  =\t05h 14m 13.99s\n    Dec (J2000.0):  -39.9927  =  -39d 59' 33.7\"\n    Error:\t    5.8 (arcsec, radius, 90% confidence).\n    Detect flag:    REASONABLE\n    Distance:\t    2.1 arcmin from the SVOM/ECLAIRs position.\n    Mean rate:\t    (-1.0 +/- -1.0)e0 ct s^-1\n    Mean flux:\t    (-2.2 +/- -2.2)e-11 erg cm^-2 s^-1\n    Peak rate:\t    (4.5 [+2.6, -2.1])e-3 ct s^-1\n    Peak flux:\t    (9.6 [+5.6, -4.4])e-14 erg cm^-2 s^-1\n    ECF:\t    2.16e-11 erg cm^-2 ct^-1\n\t\t      assuming NH=1.21e+22 cm^-2, gamma=9.85\n\t\t      determined from a spectral fit.\n    This matches a catalogued X-ray source LSXPS J051414.3-395936\n    in the LSXPS catalogue. Details:\n    Separation:     4.6\" from the XRT source\n    Cat Rate:\t    0.0e+00 +/- 2.3e-04 ct s^-1 \n    Cat Flux:\t    0.0e+00 +/- 5.1e-15 erg cm^-2 s^-1 (0.3-10 keV)\n\t\t      so the source  is 1.9-sigma above the catalogued flux.\n    There is no evidence for fading.\n\nAll fluxes are 0.3-10 keV, observed. For all flux conversions and comparisons with\ncatalogues and upper limits  from other missions, we assumed a power-law spectrum\nwith NH=3x10^20 cm^-2 and photon index (Gamma)=1.7 unless otherwise stated.\n\nThe results of the XRT-team automatic analysis of the XRT observations, including a\nposition-specific upper limit calculator, are available at\nhttps://www.swift.ac.uk/SVOM/SVOM_FIELD00030.\n\nThis circular is an official product of the Swift-XRT team.\n\n\n",
  "submittedHow": "email",
  "circularId": 41401,
  "subject": "sb25081602: Swift-XRT observations",
  "bibcode": "2025GCN.41401....1E",
  "createdOn": 1755431768350
}