[vsnet-grb-info 24763] GRB 200122A: RATIR Optical Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26862
SUBJECT: GRB 200122A: RATIR Optical Observations 
DATE:    20/01/23 04:14:06 GMT
FROM:    Alan M Watson at UNAM  <alan at astro.unam.mx>

Alan M. Watson (UNAM), Nat Butler (ASU), 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 200122A (Sonbas et al., GCN Circ. 26844)
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 2020/01 22.35 to
2020/01 22.56 UTC (6.67 to 11.76 hours after the BAT trigger), obtaining
a total of 3.76 hours exposure in the r and i bands.

For a source within the Swift-XRT enhanced error circle (Osborne et al.,
GCN Circ. 26846), in comparison with the SDSS DR9 and 2MASS catalogs, we
obtain the following 3-sigma upper limits:

  r	> 23.72
  i	> 23.42

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.