GCN Circular 12406

Subject

GRB 110928A: Swift/UVOT Upper Limits

Event

Date

2011-09-28T20:38:28Z (14 years ago)

From

Erik Hoversten at Swift/Penn State <hoversten@astro.psu.edu>

E. A. Hoversten (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 110928A
3342 s after the BAT trigger (Hoversten et al., GCN Circ. 12394Loading...
 
 ).
No optical afterglow consistent with the XRT position (Osborne et al.,
GCN Circ. 12402Loading...
 
 ) is detected in the initial UVOT exposures. Preliminary
3-sigma upper limits using the UVOT photometric system
(Poole et al. 2008, MNRAS, 383, 627) for the first finding chart (FC)
exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC          3342         3492          147         >20.2
white             3342         4723          344         >21.0
v                 3499         3698          197         >19.1
b                 4319         4518          197         >21.0
u                 4114         4313          197         >20.8
w1                3909         4108          197         >20.3
m2                3704         3903          197         >19.9
w2                4729         4929          197         >21.6

The magnitudes in the table 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).