GCN Circular 23212

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), Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:

We observed the field of GRB 180905A (D'Elia et al., GCN Circ. 23201
Not found
 
 
)
with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio
Astron��mico Nacional on Sierra San Pedro M��rtir from 2018/09 6.42 to
2018/09 6.51 UTC (20.07 to 22.23 hours after the BAT trigger), obtaining
a total of 1.17 hours exposure in the r and i bands and 0.57 hours
exposure in the Z, Y, J, and H bands.

For a source within the Swift-XRT enhanced error circle (Beardmore et
al., GCN Circ. 23207
Not found
 
 
), in comparison with the USNO-B1 and 2MASS
catalogs, we obtain the following upper limits (3-sigma):

  r	> 23.26
  i	> 23.10
  Z	> 22.21
  Y	> 22.06
  J	> 21.60
  H	> 21.25

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 Astron��mico Nacional in San Pedro
M��rtir.