Konus-Wind detection of GRB 230616A
Abstract
The short-duration, bright GRB 230616A (Swift-BAT/GUANO detection: Tohuvavohu et al., GCN Circ. 33982; AstroSat-CZTI detection: Waratkar et al., GCN Circ. 33983; IPN triangulation: Kozyrev et al., GCN Circ. 34046) triggered Konus-Wind at T0=74278.259 s UT (20:37:58.259). The burst light curve shows a multipeaked structure which starts at ~T0-30 ms and has a total duration of ~98 ms. The emission is seen up to ~7 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB230616_T74278/ As observed by Konus-Wind, the burst had a fluence of 9.11(-1.11,+1.13)x10^-6 erg/cm2, and a 16-ms peak flux, measured from T0+0.028 s, of 1.77(-0.32,+0.33)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 - 7 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -0.38(-0.15,+0.17) and Ep = 1725(-257,+286) keV (chi2 = 63/55 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.7 (chi2 = 63/54 dof). All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- June 2023
- Bibcode:
- 2023GCN.34091....1T