[vsnet-grb-info 24896] GRB 200205B: LCO Optical Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  26995
SUBJECT: GRB 200205B: LCO Optical Detection
DATE:    20/02/05 21:37:40 GMT
FROM:    Robert Strausbaugh at U. of the Virgin Islands  <robert.strausbaugh at uvi.edu>

R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (U. of the Virgin Islands/College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 200205B (Evans et al., GCN 26993) with the LCO 1-m Sinistro instrument at the South African Astronomical Observatory site on February 5, from 19:38 to 20:00 UT (corresponding to 0.28 to 0.82 hours after the GRB trigger time) with the Bessel R and I filters.

We performed a series of 5x120s exposures in each band. We detect a source that is consistent with the Swift-XRT position (Evans et al., GCN 26993) and other optical detections (Lipunov et al., GCN 26991) and not present in either USNO-B1.0 or 2MASS surveys with the following  magnitudes:

R = 18.56 +/- 0.04

I = 17.15 +/- 0.03

These magnitudes are calibrated against several USNO-B1.0 objects near the GRB location and is not corrected for Galactic Extinction.

R.S. is funded by NSF AST grant #1831682