[vsnet-grb-info 14800] GRB 140414A: Swift/UVOT Upper Limit

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16114
SUBJECT: GRB 140414A: Swift/UVOT Upper Limit
DATE:    14/04/15 21:52:27 GMT
FROM:    Frank Marshall at GSFC  <femarsha at khamseen.gsfc.nasa.gov>

F. E. Marshall (NASA/GSFC), L.M.Z. Hagen (PSU), and P. D'Avanzo (INAF-OAB)
report on behalf of the Swift/UVOT team:

The Swift/UVOT observed the field of GRB 140414A
in the U, White, and V filters starting about 40 ks
after the BAT trigger (Cummings GCN Circ. 16110).
Because the star tracker failed to lock, stars are trailed
in all the images, and the usual UVOT sensitivities
are not achieved.
No optical afterglow consistent with the BAT position
is detected in the any of the UVOT exposures.
The results for the most sensitive exposure is reported
in the table below. The limiting magnitude is
estimated from the list of detected stars.

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

white            40958        41502          536         >20

The magnitude in the table is not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).