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GCN Circular 18453

LIGO/Virgo G194575: RATIR Observations of Nearby Galaxies in the 1sigma Error Region
2015-10-23T18:18:50Z (9 years ago)
Nat Butler at Az State U <>
Nat Butler (ASU), Neil Gehrels (GSFC), V. Zach Golkhou (ASU), Alexander
Kutyrev (GSFC), William H. Lee (UNAM), Eleonora Troja (GSFC), Alan M.
Watson (UNAM) report:

We observed 26 nearby galaxies (D<10 Mpc) within the GWGC catalog (White,
et al. 2011) and also contained with the LIGO/Virgo G194575 1-sigma
confidence interval (Singer, et al. GCN 18442) between RA 23.1 hours and RA
1.5 hours (J2000) with the Reionization and Transients Infrared Camera
(RATIR; on the 1.5m Harold Johnson Telescope at the
Observatorio Astron��mico Nacional on Sierra San Pedro M��rtir on the night
of 2015/10/23.

We obtained a total exposure of 8 minutes on each field, reaching typical
depths of r and i = 21 mag, and z = 17 mag (10-sigma).  These magnitudes
are in the AB system and are not corrected for Galactic extinction.  Each
field, centered upon one GWGC galaxy, has a size of approximately 5 by 5
arcmin^2.  Analysis is ongoing.

We thank the staff of the Observatorio Astron��mico Nacional in San Pedro

Continued observations are planned.

[GCN OPS NOTE(26oct15):  In the FROM-line the SB was replaced with NB.
SB manually processed the submission due to problems with NB's entry
in the vetting list.  The record has now been corrected.]

[GCN OPS NOTE(27oct15):  The Trigger number was changed from "G19457"
to "G194575" in the Subject-line and the first paragraph.]

[GCN OPS NOTE(15jun16):  If you are looking for the V.Savchenko circ 18453
("LIGO/Virgo G194575: INTEGRAL search of temporally coincident prompt hard X-ray emission"),
please note that the ID for that circular has been changed to "18453a".]
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