[vsnet-grb-info 15295] GRB 140713A: NOT upper limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16587
SUBJECT: GRB 140713A: NOT upper limits
DATE:    14/07/14 11:21:24 GMT
FROM:    Zach Cano at U of Iceland  <zewcano at gmail.com>

​​Z. Cano (U. Iceland), D. Malesani (DARK/NBI) and M. Nielsen (Max Planck,
Gottingen) report on behalf of a larger collaboration:

We observed the field of GRB 140713A (Mangano et al., GCN Circ. 16581) with
the 2.5-m Nordic Optical Telescope (NOT) equipped with ALFOSC starting at
22:02 UT on 13-Jul-2014. We obtained 5x180 s frames in both SDSS-r and
SDSS-i, and 5x300s in SDSS-z.

No new object is found in the refined XRT error circle (Beardmore et al.,
GCN Circ. 16585) down to limiting magnitudes of:

  filter                t-t0 (hr)
---------------------------------
R (Vega) > 23.9    3.46
I (Vega)  > 23.0    3.77
z (AB)     > 22.5    4.17

The upper limits for an isolated point source in our combined images have
been determined using nearby USNO star at RA=18:44:21.50, Dec=+59:38:04.0,
which has R2=19.23, Imag=17.85, and z=17.87.  The z-band magnitude has been
determined using transformation equations from Table 3 in Jordi et al.
(2006,A&A,460,339).  These magnitudes have not been corrected for
foreground extinction.