[vsnet-grb-info 20813] GRB 180705A: RATIR Optical Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22911
SUBJECT: GRB 180705A: RATIR Optical Observations 
DATE:    18/07/06 09:19:42 GMT
FROM:    Alan M. Watson at Instituto de Astronomia 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 180705A (Stamatikos et al., GCN Circ.
22902) 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 2018/07 6.16 to
2018/07 6.27 UTC (12.19 to 14.82 hours after the BAT trigger), obtaining
a total of 1.74 hours exposure in the r and i bands.

For a source within the Swift-XRT error circle (Kennea et al., GCN Circ.
22903), in comparison with the SDSS DR9 catalog, we obtain the following
3-sigma upper limits:

  r > 23.20 
  i > 23.07

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.