GCN Circular 16341
Subject
GRB 140408A: Withdrawal of afterglow candidate
Date
2014-05-30T06:57:16Z (10 years ago)
From
Fabian Knust at MPE/GROND <fabian.knust@hotmail.de>
GRB 140408A: Withdrawal of afterglow candidate
F. Knust, K. Varela, C. Delvaux (all MPE Garching), D.A. Kann (TLS
Tautenburg) and J. Greiner (MPE Garching) report on behalf of the GROND
team:
We observed the GRB 140408A field again on further three epochs,
simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120,
405) mounted at the 2.2 m MPG telescope at ESO La Silla Observatory (Chile).
The afterglow candidate reported in Varela et al. (GCN #16089) remained
constant, thus this source is a fore- or background source and not the
afterglow of GRB 140408A.
For the first epoch as reported in Varela et al. (GCN #16089), no other
source is seen in the 1".8 Swift-XRT refined error circle
(http://www.swift.ac.uk/xrt_positions/00595141/) down to limiting magnitudes
(all in the AB system) of
g' > 25.8 mag,
r' > 25.6 mag,
i' > 25.0 mag,
z' > 25.0 mag,
J > 22.1 mag,
H > 21.5 mag, and
K > 20.0 mag.
The given limits are based on calibrating the images against GROND
zeropoints and 2MASS field stars, and are not corrected for the Galactic
foreground extinction corresponding to a reddening of E_(B-V)= 0.16 in the
direction of the burst (Schlegel et al. 1998).