[vsnet-grb-info 16539] GRB 150514A: Swift/UVOT Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17820
SUBJECT: GRB 150514A: Swift/UVOT Detection
DATE:    15/05/15 13:50:53 GMT
FROM:    Frank Marshall at GSFC  <femarsha at khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC) and J. K. Cannizzo (GSFC/UMBC)
report on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 150514A
40750 s after the LAT trigger (Kocevski and Arimoto, GCN Circ. 17816).
A source consistent with the XRT position (Kennea et al. GCN Circ. 17818)
is detected in the initial UVOT exposures.

The preliminary UVOT position is:
    RA  (J2000) =  04:59:30.30 =  74.87623 (deg.)
    Dec (J2000) = -60:58:06.3  = -60.96841 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).

Preliminary detections using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: 

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

white            41402        41850          440         18.60 +/- 0.04
v                42049        42222          170         18.71 +/- 0.20
u                40750        41396          636         18.20 +/- 0.05

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).