[vsnet-grb-info 15703] GRB 141028A: Continued RATIR Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16991
SUBJECT: GRB 141028A: Continued RATIR Observations
DATE:    14/10/30 16:13:49 GMT
FROM:    Eleonora Troja at GSFC  <eleonora.troja at nasa.gov>

Eleonora Troja (GSFC), 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), 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 141028A (Bissaldi, et al., GCN 16969) 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 2014/10 30.08 to 2014/10 30.31 UTC (39.07
to 44.46 hours after the GBM trigger), obtaining a total of 4.24 hours
exposure in the r, i, and z bands.

For a source within the enhanced XRT error circle (Pagani et al., GCN 
16986),
in comparison with the SDSS DR9, we obtain the following detections:

   r    21.19 ± 0.04
   i    20.79 ± 0.03
   z    20.74 ± 0.24

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.  A comparison to our previous
observations (Troja et al., GCN 16980) shows that the afterglow faded 
with a
power-law decay index of alpha ~ 0.9 in all three filters, consistent 
with the decay
reported by Cenko & Perley (GCN 16989).

Further observations are planned.

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