GCN Circular 9048
Subject
GRB 090328: Swift UVOT observations
Event
Date
2009-03-29T15:11:20Z (17 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began observing the field of GRB 090328 16 hrs
after the Fermi LAT trigger (McEnery et al., GCN 9044). We detect
a candidate optical afterglow in the u and white filters at:
RA(J2000.0) = 06:02:39.67
DEC(J2000.0) = -41:52:54.5
with an estimated uncertainty of 0.6 arcsec (radius, 90% confidence).
At the moment we are unable to tell if the source is fading, further
observations have been performed, but due to a data gap, the data
is currently unavaliable.
Preliminary magnitudes for the white and u filters are:
Filter T_mid (hrs) Exposure(s) Mag Err
------------------------------------------------------------
u 16.0 793 19.04 +/- 0.13
white 16.1 173 19.56 +/- 0.14
The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.06 mag (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT flight system
described in Poole et al. (2008, MNRAS, 383,627).