GRB 191004A: Optical Detection with LCO
Abstract
We observed Swift GRB 191004A (Barthelmy et al., GCN 25945) with the LCO 1-m Sinistro instrument on September 4, from 20:12 to 20:47 UT (corresponding to 1.70 to 2.28 hours from the GRB trigger time) with the Bessel R and I filters. We performed a series of 10x180s exposures in each band. We do not detect a significant source in individual frames, but we do detect a source in co-added frames that is not present in either USNO-B1.0 or 2MASS surveys and is consistent with the optical afterglow location (Evans et al., GCN 25950) with the following magnitudes: R = 22.89 +/- 0.10 I = 21.00 +/- 0.09 This flux is calibrated against several USNO-B1.0 objects near the GRB location but is not corrected for Galactic Extinction. These observations were possible thanks to the USVI NASA-EPSCoR Research Infrastructure Development (RID) grant NNX16AL44A.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- October 2019
- Bibcode:
- 2019GCN.25971....1S