[vsnet-grb-info 21213] GRB 181010A: RATIR Optical and NIR Afterglow Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  23312
SUBJECT: GRB 181010A: RATIR Optical and NIR Afterglow Detection
DATE:    18/10/10 08:02:49 GMT
FROM:    Eleonora Troja at GSFC  <eleonora.troja at nasa.gov>

Eleonora Troja (GSFC), 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), Owen Littlejohns
(ASU), Enrico Ramirez-Ruiz (UCSC), Jesus Gonzalez (UNAM),
Carlos Román-Zuniga (UNAM), Harvey Moseley (GSFC), John
Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD)
report:

We observed the field of GRB 181010A (Melandri, et al., GCN 23309)
with the Reionization and Transients Infrared Camera (RATIR;
www.ratir.org) on the 1.5m Harold Johnson Telescope at the
Observatorio Astronomico Nacional on Sierra San Pedro Martir from
2018/10 10.25 to 2018/10 10.29 UTC (4.2 min to 1.10 hours after
the BAT trigger), obtaining a total of 0.50 hours exposure in the
r and i bands and 0.24 hours exposure in the Z, Y, J, and H bands.

At the position of the optical afterglow (Melandri, et al.,
GCN 23309; Gorbovskoy, et al., GCN 23310), in comparison with the
USNO-B1 and 2MASS catalogs, we obtain the following detections:

r    20.30 +/- 0.20
i    21.03 +/- 0.10
Z    20.67 +/- 0.24
Y    20.24 +/- 0.21
J    19.87 +/- 0.24
H   19.16 +/- 0.17

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 Astronomico Nacional in
San Pedro Martir.

Further observations are on-going.