GCN Circular 14370
Subject
GRB130408A: Swift/UVOT followup observations
Event
Date
2013-04-09T11:07:36Z (13 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. Breeveld (MSSL/UCL) and A. Y. Lien (NASA/GSFC/ORAU) report on behalf
of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 130408A
134 s after the BAT trigger (Lien et al., GCN Circ. 14361). A bright but
rapidly fading source is detected in the initial exposures (Siegel and
Lien, GCN Circ. 14363) with a position consistent with detections by
Melandri et al., (GCN Circ., 14362), Sudilovsky et al., (GCN Circ.,
14364) and Beardmore et al., (GCN Circ. 14367).
The preliminary UVOT position is:
RA(J2000) = 08:57:37.30 = 134.40540
DEC(J2000) = -32:21:38.9 = -32.36081
with a 90%-confidence error radius of about 0.5 arc sec.
Preliminary detections and 3-sigma upper limits using the UVOT
photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for
the early and summed exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 156 305 147.4 16.80 � 0.05
white 3708 3900 189.2 20.29 � 0.22
white 6083 10367 924.3 21.99 � 0.35
v 134 145 10.1 15.75 � 0.15
v 4201 4400 196.7 19.61 � 0.35
b 3503 6078 393.2 >20.84
u 313 5872 236.2 >20.55
uvw1 4611 4752 139.0 >19.82
uvm2 4405 4605 196.6 >19.75
uvw2 3996 21851 1748.0 >21.56
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.258 in the direction of
the burst (Schlegel et al. 1998).