TITLE:   GCN CIRCULAR
NUMBER:  38110
SUBJECT: GRB 241105A: Swift/UVOT Detection
DATE:    24/11/07 13:18:53 GMT
FROM:    Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>

M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 241105A
38.4 ks after the Fermi trigger (GCN Circ. 38085). A faint fading source
is detected consistent with the XRT position (Kennea et al., GCN Circ. 38098)
and the reported optical counterparts (Julakanti et al., GCN Circ. 38088, Izzo, 
GCN. Circ. 38097, Wei et al., GCN Circ. 38099, Hu et al., GCN Circ 38106).

The preliminary UVOT position is:
    RA  (J2000) =  04:24:58.96 =  66.24568 (deg.)
    Dec (J2000) = -49:45:09.8  = -49.75271 (deg.)
with an estimated uncertainty of 0.42 arc sec. (radius, 90% confidence).
  
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:

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

white            38363        67383         4551      21.46+/-0.11
white            90644       106641         4612            >22.76

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.011 in the direction of the burst
(Schlegel et al. 1998).