[vsnet-grb-info 12464] GRB 121001A: Swift/UVOT Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  13839
SUBJECT: GRB 121001A: Swift/UVOT Upper Limits
DATE:    12/10/02 17:12:45 GMT
FROM:    Frank Marshall at GSFC  <femarsha at khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and V. D'Elia (ASDC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 121001A
130 s after the BAT trigger (D'Elia et al., GCN Circ. 13831).
No optical afterglow consistent with the optical position
(Tello et al. GCN Circ. 13835) 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) exposures and subsequent exposures are:

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

white_FC           130          280          147         >21.0
u_FC               288          538          246         >20.0
white              130         7415          824         >22.4
v                  618         6390          352         >20.2
b                  544         7210          526         >21.2
u                  288         7005          756         >20.7
w1                 668         6800          529         >20.4
w2                 767         7608          439         >21.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 1.36 in the direction of the burst
(Schlegel et al. 1998).