TITLE:   GCN CIRCULAR
NUMBER:  16458
SUBJECT: GRB 140626A: GROND Afterglow Candidate
DATE:    14/06/26 02:43:50 GMT
FROM:    Alexander Kann at TLS Tautenburg  <kann@tls-tautenburg.de>

M. Tanga, J. F. Graham (both MPE Garching), D. A. Kann (TLS Tautenburg),
and J. Greiner (MPE Garching) report on behalf of the GROND team:

We observed the field of GRB 140626A (Swift trigger 602604; Cummings et
al., GCN #16456) 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).

Observations started at 00:45:12 UT on June 26, 2014, 12 minutes after the
GRB trigger. They were performed at an average seeing of 2.4 and at an
average airmass of 2.5.

We detect a source at the north-eastern edge of the the Swift-XRT error
circle reported by Cummings et al., GCN #16456 at RA (J2000) =
05:09:30.79, Dec. (J2000) = -82:37:50.2, at AB magnitude:

g' = 21.9 +/- 0.1 mag,
r' = 20.9 +/- 0.1 mag,
i' = 20.4 +/- 0.1 mag, and
z' = 19.8 +/- 0.1 mag.

This object is not detected in the DSS. We propose it to be the afterglow
of GRB 140626A but at this time cannot ascertain fading.

The magnitude was derived based on calibrating the image against the GROND
zeropoint and is not corrected for the Galactic foreground extinction
corresponding to a reddening of E_(B-V)= 0.15 mag in the direction of the
burst (Schlegel et al. 1998).

[GCN OPS NOTE(26jun14): Per author's request, the typo of the observation
date in the second paragraph was changed from Jun 22 to Jun 26.]