[vsnet-grb-info 4348] RHESSI Spectrum of GRB070220

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  6135
SUBJECT: RHESSI Spectrum of GRB070220
DATE:    07/02/23 18:32:12 GMT
FROM:    Eric Bellm at UCB/SSL  <ebellm at ssl.berkeley.edu>

C. Wigger, E. Bellm, M. Bandstra, S. Boggs, W. Hajdas,
D. M. Smith, and K. Hurley on behalf of the RHESSI team report:

As observed by RHESSI, GRB070220 (M. Stamatikos et al., GCN 6114)
had a duration of ~30s starting at about T0=04:44:33 UT.
A fit to the time-integrated RHESSI spectrum of the main period of
emission from T0 - T0+18s between 30 keV and 3.0 MeV gives a
cutoff power law, with

alpha = -0.65 +0.40/-0.35
E0 = 235 +180/-90 keV
Epeak = 315 +115/-70 keV
(90% confidence levels).

The 20 keV-2 MeV fluence is (1.14 +0.16/-0.12) E-5 erg/cm^2.