{
  "bibcode": "2020GCN.27667....1R",
  "body": "A. Ridnaia, S. Golenetskii, R. Aptekar, D. Frederiks,\nM. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline\non behalf of the Konus-Wind team, report:\n\nThe onset of a new period of activity of SGR 1935+2154\n(Swift-BAT detection: Barthelmy et al., GCN Circ. 27657,\nPalmer, GCN Circ. 27665;\nFermi-GBM observation: Fletcher, GCN Circ. 27659;\nMAXI-GSC detection: Sugawara et al., GCN Circ. 27661;\nCALET-GBM observation: Ricciarini et al., GCN Circ. 27663;\nAstroSat-CZTI detection: Marathe et al., GCN Circ. 27664)\nhas been detected by Konus-Wind on 2020 April 27.\n\nA series of several tens of bursts triggered Konus-Wind at\n66696.729 s UT (18:31:36.729). The series consists of\ntwo very crowded clusters:\nfrom -0.252 s to 8 s and\nfrom 77 s to 116 s relative to the trigger time\n(numerous weaker bursts are seen between intense bursts).\n\nThe most intense episode of the cluster started at ~85 s\nafter trigger time. It had a duration of ~23.6 s,\na fluence of 1.09(-0.02,+0.02)x10^-4 erg/cm2,\nand a 64-ms peak flux, measured from T0+95.680 s,\nof 2.28(-0.27,+0.29)x10^-5 erg/cm2/s\n(both in the 20 - 200 keV energy range).\n\nThe time-integrated spectrum of this cluster\n(measured from T0+74.496 to T0+91.392)\nis well fit by a power law with exponential cutoff model:\ndN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)\nwith  alpha = -0.48(-0.17,+0.18)\nand Ep = 35(-1,+1) keV (chi2 = 47/29 dof).\nA double blackbody function fits this spectrum equally well\n(chi2 = 38/28 dof), with\nthe cold BB temperature of 4.7 (-0.5,+0.6) keV and\nthe hot BB temperature of 12.5 (-0.4,+0.5) keV.\n\nThe Konus-Wind light curve of this trigger is available at\nhttp://www.ioffe.ru/LEA/SGRs/200427_T66696/\n\nFurther SGR 1935+2154 bursts have triggered KW on 2020\nApril 27, so far, at 71024.348 s UT (19:43:44.348),\n79162.174 s UT (21:59:22.174), and 85471.654 s UT\n(23:44:31.654).\n\nThis burst cluster resembles the series of bursts from\nSGR 1900+14 and SGR 1806-20 detected about three months\nbefore giant flares from these sources observed on\n1998 August 27 and 2004 December 27, respectively\n(Aptekar et al., ApJSS v. 137, p. 227, 2001, Golenetskii\net al., GCN Circ. 2769, Golenetskii et al., GCN Circ. 2896).\n\nAll the quoted errors are at the 90% confidence level.\nAll the quoted values are preliminary.",
  "circularId": 27667,
  "createdOn": 1588099648000,
  "email": "ridnaia@mail.ioffe.ru",
  "subject": "Konus-Wind observation of a very intense bursting activity of SGR 1935+2154",
  "submitter": "Anna Ridnaia at Ioffe Institute  <ridnaia@mail.ioffe.ru>",
  "eventId": "SGR 1935+2154"
}