GCN Circular 4779
Subject
Further UVOT Observations of the Candidate Optical Afterglow for GRB 060218
Event
Date
2006-02-18T17:01:28Z (20 years ago)
From
Frank Marshall at GSFC <marshall@milkyway.gsfc.nasa.gov>
F. Marshall (GSFC), S. Immler (GSFC/USRA) and G. Cusumano (IASF-Pa INAF)
report on behalf of the Swift team:
The UVOT source reported by Cusumano et al. (GCN 4775) is detected in all
four UVOT finding chart exposures ranging from 153s to 1036s
from the burst trigger as shown in the table below. There is marginal
evidence for brightening in the V filter. The revised source position is
03:21:39.71 +16:52:02.6 (J2000) with an estimated 1-sigma error of about 1.0".
This position is within the XRT error circle (Kennea et al. GCN 4776).
We note the existence of a source in the USNO-B1 catalog
at 03:21:39.69 +16:52:02.2 with a B2 magnitude of 20.67
and an R2 magnitude of 20.3. Further UVOT observations
are underway to search for fading of this afterglow candidate.
T_start Exposure Filter Mag Mag. Range (1-sigma)
153 200 V 19.6 19.1 - 20.3
359 155 B 19.4 19.2 - 19.6
830 127 B 19.3 19.1 - 19.5
1036 148 V 18.4 18.2 - 18.6