[vsnet-grb-info 21074] GRB 180823A: RATIR Optical and NIR Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23172
SUBJECT: GRB 180823A: RATIR Optical and NIR Observations
DATE:    18/08/24 14:46:19 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), Ori Fox (STScI), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora
Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús
González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John
Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:

We observed the field of GRB 180823A (Sbarufatti, et al., GCN 23169) 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 2018/08 24.14 to 2018/08 24.19 UTC (8.40 to
9.45 hours after the BAT trigger), obtaining a total of 0.40 hours exposure
in the r and i bands and 0.29 hours exposure in the Z, Y, J, and H bands.

For a source within the Swift-XRT error circle (Evans, et al., GCN 23170),
in comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following
upper limits (3-sigma):

 r > 22.20
 i > 22.05
 Z > 20.84
 Y > 19.72
 J > 20.45
 H > 19.12

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

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