[vsnet-grb-info 6577] GRB 080825C: Fermi GBM Spectral Analysis

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8184
SUBJECT: GRB 080825C: Fermi GBM Spectral Analysis
DATE:    08/09/05 18:01:27 GMT
FROM:    Alexander van der Horst at NASA/MSFC  <avdhorst at science.uva.nl>

A.J. van der Horst (NASA/ORAU), V. Connaughton and M.S. Briggs (UAH)
report on behalf of the Fermi GBM Team:

"We have performed time-resolved spectroscopy of GRB 080825C (GCN 8141,
GCN 8183). The main emission up to 23 seconds is best fit by the Band
function. Time-resolved spectra of this emission period display the
commonly observed hard-to-soft spectral evolution, with Epeak decreasing
from 170 to 110 keV, while the spectral indices remain roughly constant
at alpha ~ -0.4 and beta ~ -2.4, consistent with the time-averaged
spectral result (GCN 8141).
Weaker emission following this period lasts a further 11 seconds and
deviates from this spectral behaviour. The spectrum of this tail over
the energy range 8-900 keV is best fit by a single power law with
index -1.41 +/- 0.09.

The spectral analysis results presented above are preliminary; the final
results will be published in the GBM GRB Catalog."