Skip to main content
Announcing GCN Classic Migration Survey, End of Legacy Circulars Email. See news and announcements

GCN Circular 9846

Subject
GRB 090827 Burst discovered in BAT ground analysis
Date
2009-08-28T20:39:11Z (15 years ago)
From
Jay R. Cummings at NASA/GSFC/Swift <jayc@milkyway.gsfc.nasa.gov>
J. R. Cummings (GSFC/UMBC), H. A. Krimm (GSFC/USRA),
C. B. Markwardt (GSFC/UMD), and D. M. Palmer (LANL),
on behalf of the Swift-BAT team

At 19:06:26 on 2009-08-27, GRB 090827 triggered Swift-BAT
(trigger #361029). No source was found onboard.  A source
was found in ground analysis of BAT event data.  The burst
consisted of a single pulse of 7 seconds.  This burst also
triggered Konus-Wind and INTEGRAL-SPI-ACS (V. Pal'shin,
private communication).

The BAT position is RA, Dec 18.435, -50.899, which is
equivalent to:

       RA, Dec (J2000): 01:13:44.4, -50d 53' 58"  	

with an uncertainty radius of 2.8 arcmin (estimated 90%
containment, stat+sys). The source was 3% coded.

Because of the extreme partial coding, the spectral parameters
can be defined only poorly.  The spectrum is best fit by a
simple powerlaw relation.  The photon index is 1.0 +/- 0.3.
The fluence was (4 +/- 2) x 10^-6 ergs/cm2. The errors are
estimated 1-sigma.

A Swift TOO has been requested and will take place
starting approximately 26 hours after the burst.
Looking for U.S. government information and services? Visit USA.gov