[vsnet-grb-info 14898] GRB 140430A: NOT optical observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16193
SUBJECT: GRB 140430A: NOT optical observations
DATE:    14/04/30 23:43:05 GMT
FROM:    Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst  <malesani at dark-cosmology.dk>

D. Malesani (DARK/NBI), T. Kruehler (ESO Santiago), A. de Ugarte Postigo 
(IAA/CSIC and DARK/NBI), H. Dahle (Univ. Oslo), E. Soto (CUA), report on 
behalf of a larger collaboration:

We observed the optical afterglow of GRB 140430A (Siegel et al., GCN 
16190; Melandri et al., GCN 16192) with the Nordic Optical Telescope 
equipped with ALFOSC. We took a single 100-s image in the R filter 
starting at 22:00 UT (86.5 min after the GRB). The optical afterglow is 
well detected at coordinates (J2000):

RA = 06:51:44.61
Dec = +23:01:25.1

with an uncertainty of 0.3". Assuming R = 15.13 for the USNO star at RA 
= 06:51:41.3, Dec = +23:01:44.0, we measure for the optical afterglow a 
magnitude R = 18.78 +- 0.02 (statistical error only).

A 1800-s spectrum was acquired starting at 22:11 UT, at airmass 2.2-2.8, 
covering the wavelength range 3200-9100 AA. From a preliminary analysis, 
no absorption or emission features are seen in the spectrum. From the 
lack of a DLA feature down to ~4000 AA, we can set a redshift limit z < 2.3.