{
  "submitter": "Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>",
  "createdOn": 1791811688923,
  "body": "D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,\nA. Tsvetkova,  M. Ulanov, and T. Cline,\non behalf of the Konus-Wind team, report:\n\nThe long-duration GRB 261007A (\nSVOM detection: Goto et al., GCN 45824;\nEinstein Probe detection of an X-ray transient: Wen et al., GCN 45828;\nFermi-GBM observation: Malacaria, GCN 45830;\nNuSTAR detectuin: Waratkar & Grefenstette, GCN 45846;\nAstroSat-CZTI detection: Harsha et al., GCN 45859;\nSVOM-GRM observation: Ren et al., GCN 45863;\nGlowbug detection: Cheung et al., GCN 45867)\ntriggered Konus-Wind (KW) at T0=20393.695 s UT (05:39:53.695).\n\nThe burst light curve shows a bright multipeaked structure\nin the interval from ~T0-1.2 s to ~T0+32 s.\nThe emission is seen up to ~10 MeV.\n\nThe Konus-Wind light curve of this GRB is available at\nhttp://www.ioffe.ru/LEA/GRBs/GRB261007_T20393/\n\nAs observed by Konus-Wind, the burst had\nthe fluence of (9.36 ± 0.30)x10^-5 erg/cm^2 and\nthe 64-ms peak energy flux, measured from T0 + 21.996 s,\nof (1.41 ± 0.09)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).\n\nThe time-integrated spectrum of the burst (measured from T0 to T0+32 s)\nis best fit in the 20 keV - 15 MeV range by a GRB (Band) function\nwith the following model parameters:\nthe low-energy photon index alpha = -0.53 (-0.04,+0.04),\nthe high energy photon index beta = -2.87 (-0.15,+0.12),\nthe peak energy Ep = 273 (-8,+8) keV,\nchi2 = 89/97 dof.\n\nThe spectrum near the peak count rate (measured from T0+19.712 s to T0+23.808 s)\nis best fit in the 20 keV - 15 MeV range by a GRB (Band) function\nwith the following model parameters:\nthe low-energy photon index alpha = -0.52 (-0.07,+0.07),\nthe high energy photon index beta = -2.73 (-0.15,+0.12),\nthe peak energy Ep = 245 (-11,+11) keV,\nchi2 = 61/73 dof.\n\nAssuming the redshift z=2.101 (Saccardi et al., GCN 45829)\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 burst isotropic energy release E_iso to (1.04 ± 0.03)x10^54 erg,\nthe isotropic peak luminosity L_iso to (8.84 ± 0.31)x10^53 erg/s, and\nthe rest-frame peak spectral energy Ep,z to (847 ± 25) keV.\nWith the obtained estimates, GRB 261007A is consistent with 68% prediction bands\nfor both 'Amati' and  'Yonetoku' relations for the sample of >300 long KW GRBs\nwith known redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021),\nsee http://www.ioffe.ru/LEA/GRBs/GRB261007_T20393/GRB261007A_rest_frame.pdf\n\nAll the quoted errors are estimated at the 68% confidence level.\nAll the presented results are preliminary",
  "subject": "Konus-Wind detection of GRB 261007A/EP261007a",
  "eventId": "GRB 261007A",
  "submittedHow": "email",
  "circularId": 45923
}