{
  "subject": "Konus-Wind detection of GRB 241025A",
  "submittedHow": "web",
  "bibcode": "2024GCN.37927....1S",
  "createdOn": 1730126038758,
  "format": "text/plain",
  "circularId": 37927,
  "body": "D. Svinkin, D. Frederiks, A. Lysenko, A. Ridnaia,\nA. Tsvetkova,  M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 241025A\n(Swift-BAT detection: Ambrosi et al., GCN 37859;\nFermi-GBM detection: Fermi GBM team, GCN 37860;\nGodwin, GCN 37886;\nSVOM-GRM detection: Wang et al., GCN 37863;\nEP-WXT detection: Li et al., GCN 37864)\nwas detected by Konus-Wind (KW) in the waiting mode\nat T0~5786 s UT (01:36:26).\n\nA Bayesian block analysis of the KW  waiting mode data\nin the 20-300 keV band reveals a >20 sigma count rate\nincrease in the interval from T0-13 s to ~T0+128 s.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB241025A/\n\nThe total burst fluence is 1.58(-0.14,+0.14)x10^-5 erg/cm^2,\nand the 2.944 s peak energy flux, measured from T0+0.143 s,\nis 4.5(-0.5,+0.5)x10^-7 erg/cm^2.\n(both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum of the burst,\nmeasured from T0-13 s to T0+128 s,\ncan be described by a power law with exponential cutoff (CPL) model\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith alpha = -0.85(-0.13,+0.15) and Ep = 238(-33,+38) keV.\n\nThe spectrum near the peak count rate, measured from T0+12 s to T0+30 s,\ncan be described by a CPL model with\nalpha = -0.04(-0.17,+0.20) and Ep = 261(-23,+24) keV.\n\nAssuming the redshift z=4.20 (Xu et al., GCN 37866)\nand a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315,\nand Omega_Lambda = 0.685 (Planck Collaboration, 2014),\nwe estimate the following rest-frame parameters:\nthe isotropic energy release E_iso is (5.5+/-0.5)x10^53 erg,\nthe peak luminosity L_iso is (8.2+/-0.9)x10^52 erg/s,\nthe rest-frame peak energy of the time-averaged spectrum\nEp,i,z is (1238+/-182) keV, and the spectrum near the maximum count rate \nEp,p,z is (1357+/-120) keV.\n\nWith the obtained estimates, GRB 241025A is inside 68% prediction bands for \n'Amati' and 'Yonetoku' relations for the sample of >300 long KW GRBs with \nknown redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021), \nsee http://www.ioffe.ru/LEA/GRBs/GRB241025A/GRB241025A_rest_frame.pdf\n\nAll the quoted errors are estimated at the 68% confidence level.\nAll the presented results are preliminary.",
  "eventId": "GRB 241025A",
  "submitter": "Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>"
}