[vsnet-grb-info 14623] GRB 140304A: Continued RATIR Optical and NIR Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15937
SUBJECT: GRB 140304A: Continued RATIR Optical and NIR Observations
DATE:    14/03/06 16:57:05 GMT
FROM:    Nat Butler at Az State U  <natbutler at asu.edu>

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús
González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of GRB 140304A (Evans, et al., GCN 15915) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on
Sierra San Pedro Mártir from 2014/03 6.12 to 2014/03 6.14 UTC (37.55 to
38.08 hours after the BAT trigger), obtaining a total of 0.36 hours
exposure in the r and i bands and 0.15 hours exposure in the Z,
Y, J, and H bands.

For a source within the Swift-XRT error circle, in comparison with the SDSS
DR9 and 2MASS, we obtain the following detection and upper limits (3-sigma):

  r     > 22.77
  i     > 22.60
  Z     20.88 +/- 0.20
  Y     > 20.96
  J     > 20.65
  H     > 20.31

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.  In the Z-band, the source has
faded as a powerlaw t^(-1.3) relative to our observations conducted last
night (Butler et al., GCN 15928).

We thank the staff of the Observatorio Astronómico Nacional in San Pedro
Mártir.