GCN Circular 10736
Subject
GRB100508A: Further Swift/UVOT Observations
Event
Date
2010-05-10T13:38:18Z (16 years ago)
From
Wayne Landsman at GSFC/SSAI <wayne.b.landsman@nasa.gov>
W.B. Landsman (GSFC) and R. Margutti (INAF-OAB) report on behalf of
the Swift/UVOT team.
Swift/UVOT has continued observations of GRB100508A through 93,000s
after the initial trigger (Margutti et al. GCN 10728). The afterglow
reported by Landsman and Margutti (GCN 10730) was not detected in any
filter past 12,000s after the initial trigger. Magnitudes and 3
sigma upper limits for selected exposures are reported below:
FILTER T_start(s) Exposure Mag/3UL
=================================================
white fc 152 147 18.91 � 0.07
white 864 147 20.70 � 0.31
white 11708 295 21.22 � 0.30
u 310 246 19.16 � 0.15
u 6860 197 20.12 � 0.36
b 5634 197 > 20.7
v 6250 197 > 19.7
================================================
At late times our 3" photometry aperture includes the galaxy reported
by Schady et al. (GCN 10734), which may be the GRB host. This galaxy
is also listed in the SuperCosmos Sky Survey (
http://www-wfau.roe.ac.uk/sss/docs.html ) with coordinates 2.1" distant
from the UVOT position. The late-time white magnitude in a 6491s
summed exposure taken between 57097s and 93249s after the trigger within
the 3" aperture used to measure the afterglow is 21.86 � 0.12.
There are no detections or interesting magnitude limits in the UV filters.
The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E(B-V) = 0.029 (Schlegel et al., 1998,
ApJS, 500, 525). There was a typo in the value of E(B-V) reported for
this burst by Landsman & Margutti (GCN 10730). The photometry is on
the UVOT photometric system described in Poole et al. (2008, MNRAS,
383, 627).