GCN Circular 9006
Subject
Further Swift/UVOT observations of GRB 090313
Date
2009-03-16T20:55:05Z (15 years ago)
From
Patricia Schady at MSSL/Swift <ps@mssl.ucl.ac.uk>
P.Schady (MSSL-UCL), F.E.Marshall (NASA/GSFC) and J. Mao (INAF-OAB) report
on behalf of the Swift/UVOT team:
Following on from GCN 8990 (Schady et al.), we report on Swift/UVOT
observations of GRB 090313 for all optical and ultraviolet filters. A
fading source is detected in the v filter and marginally in the b-band
filter at a position consistent with the optical afterglow reported by
Chornock et al. (GCN 8979). These observations are in agreement with the
spectroscopic redshift z=3.375 (Chornock et al., GCN 8994).
The magnitudes and 3-sigma upper limits for GRB 090313 within each
co-added UVOT filter are as follows:
Filter T_mid (hrs) Exp (s) Mag/3-sigma UL
v 11.0 551 20.10 +/- 0.30 (3.6 sigma)
b 11.2 770 21.50 +/- 0.38 (2.8 sigma)
u 8.1 1024 > 21.44
uvw1 8.6 1771 > 21.78
uvm2 9.3 886 > 21.22
uvw2 10.9 886 > 21.58
where T_mid is the weighted mean time of the observations. The values
quoted above are not corrected for the Galactic extinction due to the
reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al.
1998). All photometry is on the UVOT photometry system described in Poole
et al. (2008, MNRAS, 383, 627).
In addition, we note an error in GCN 8990 (Schady et al.), where we
mistakenly labelled the results for the u filter as b and vice versa.