[vsnet-grb-info 27740] GRB 210419C: RATIR Optical and NIR Upper Limits

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  29843
SUBJECT: GRB 210419C: RATIR Optical and NIR Upper Limits
DATE:    21/04/20 16:34:17 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 210419C (Moss, et al., GCN 29834) with the
Reionization and Transients Infrared Camera (RATIR) on the 1.5m Harold
Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San
Pedro Mártir from 2021/04 20.14 to 2021/04 20.50 UTC (2.58 to 11.15 hours
after the BAT trigger), obtaining a total of 4.53 hours exposure in the r
and i bands and 1.89 hours exposure in the Z, Y, J, and H bands.

We do not detect any sources within the enhanced XRT error region
(Beardmore, et al. GCN 29839).  In comparison with the SDSS DR9 and 2MASS
catalogs, we obtain the following upper limits (3-sigma):

  r     > 23.60
  i     > 23.53
  Z     > 22.31
  Y     > 20.10
  J     > 22.21
  H     > 21.87

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.