GCN Circular 19963

Subject

GRB 160927A: Swift/UVOT Upper Limits

Event

Date

2016-09-28T16:13:58Z (9 years ago)

From

Paul Kuin at MSSL <npkuin@gmail.com>

Paul Kuin(MSSL-UCL) and S. L. Gibson (U. Leicester)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 160927A
85 s after the BAT trigger (Gibson et al., GCN Circ. 19952Loading...
 
 ).
No optical afterglow consistent with the optical position
(D'Avanzo et al. GCN Circ. 19956Loading...
 
 )
is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

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

white_FC            85          235          147         >21.0
u_FC               297          547          246         >20.4
white               85        13184         1426         >21.8
v                  627         6999          510         >19.9
b                  553        12500         1179         >21.5
u                  297        11587         1433         >21.1
w1                 850         7411          491         >20.2
m2                 826         7204          294         >20.5
w2                 602         6794          510         >21.0

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.08 in the direction of the burst
(Schlegel et al. 1998).