{
  "eventId": "GRB 260101A",
  "bibcode": "2026GCN.43389....1S",
  "format": "text/plain",
  "subject": "Konus-Wind detection of GRB 260101A",
  "createdOn": 1768318308950,
  "submitter": "Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>",
  "circularId": 43389,
  "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 260101A\n(Fermi-GBM detection: The Fermi GBM team, GCN 43284;\nHristov and Meegan, GCN 43297;\nSwift-BAT detection: Cenko et al., GCN 43285;\nMarkwardt et al., GCN 43354;\nSVOM-GRM detection: Yu et al., GCN 43292;\nGECAM-B detection: Wang et al., GCN 43294)\ntriggered Konus-Wind at T0=3419.619 s UT (00:56:59.619).\n\nThe burst light curve shows a multipeaked structure\nwhich starts at ~T0-26 s and has a total duration of ~30 s.\nThe emission is seen up to ~1 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB260101_T03419/\n\nAs observed by Konus-Wind, the burst\nhad the total fluence of 7.47(-0.65,+0.77)x10^-6 erg/cm2,\nand the 64-ms peak flux, measured from T0+0.210 s,\nof 1.95(-0.42,+0.44)x10^-6 erg/cm2/s\n(both in the 20 keV - 10 MeV energy range).\n\nSince the main fraction of burst counts was\ndetected before the trigger, the spectral analysis\nwas performed using the KW 3-channel light curve data.\n\nModelling the KW 3-channel time-integrated spectrum\n(measured from T0-26.365 s to T0+3.168 s)\nby a power law with exponential cutoff (CPL) model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep),\nyields alpha = -1.50(-0.11,+0.13) and Ep = 176(-30,+45) keV.\n\nModelling the KW 3-channel spectrum near the maximum count rate\n(measured from T0-5.757 s to T0+3.168 s)\nby the CPL model yields\nalpha = -1.44(-0.15,+0.20) and Ep = 129(-18,+25) keV.\n\nAssuming the redshift z=2.623 (de Ugarte Postigo et al., GCN 43287)\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 1.21(-0.11,+0.12)x10^53 erg,\nthe peak luminosity L_iso is 1.15(-0.25,+0.26)x10^53 erg/s,\nthe rest-frame peak energy of the time-averaged spectrum\nEp,i,z is 637(-109,+162) keV and the spectrum near the maximum count rate \nEp,p,z is 467(-65,+90) keV.\n\nWith the obtained estimates, GRB 260101A is inside 68% prediction bands for both \nthe 'Amati' and the 'Yonetoku' relations derived 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/GRB260101_T03419/GRB260101A_rest_frame.pdf\n\nAll the quoted errors are at the 68% confidence level.\nAll the quoted values are preliminary. ",
  "submittedHow": "web"
}