GCN Circular 4787
Subject
Oddball GRB 060218, transient or GRB?
Event
Date
2006-02-19T21:49:58Z (20 years ago)
From
Neil Gehrels at GSFC <gehrels@gsfc.nasa.gov>
N. Gehrels (NASA-GSFC) on behalf of the Swift team:
We point out that GRB 060218 (Cusumano et al. GCN 4775) is a
strange event. It has
- a gamma-ray light curve that is flat and a soft spectrum
(Barbier et al. GCN 4780)
- an X-ray light curve with a long, slow rise and gradual
decline (Cusumano et al. GCN 4786)
- an optical light curve with brightening after 10 hours
(Marshall et al. GCN 4785).
These characteristics are unlike previous GRBs.
It has properties that are also atypical of a transient:
- it is far off the galactic plane (b = -32.9 deg) and
far away from the bulge (l = 166.9 deg)
- there is a possible association (Mirabel GCN 4783) with
a galaxy in the SDSS pre-burst field (Cool et al. GCN 4777).
Further observations are warranted.