Konus-Wind observation of GRB 201227A
Abstract
The short-duration, very bright GRB 201227A (AGILE detection: Ursi et al., GCN Circ. 29179; IPN triangulation: Svinkin et al., GCN Circ. 29182; Insight-HXMT/HE detection: Xiao et al., GCN Circ. 29187) triggered Konus-Wind at T0=54846.705 s UT (15:14:06.705). The burst light curve shows a multipeaked structure which starts at ~T0-28 ms and has a total duration of ~106 ms. The emission is seen up to ~4 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB201227_T54846/ As observed by Konus-Wind, the burst had a fluence of 4.30(-0.52,+0.54)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0, of 1.05(-0.18,+0.18)x10^-4 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the burst (measured from T0 to T0+0.064 s) is best fit in the 20 keV - 4 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.17(-0.18,+0.21) and Ep = 870(-130,+151) keV (chi2 = 17/19 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.3 (chi2 = 17/18 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- December 2020
- Bibcode:
- 2020GCN.29196....1S