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GCN Circular 31481

GRB 220117A: LCO Optical Observations
2022-01-18T13:39:22Z (2 years ago)
Robert Strausbaugh at U. of the Virgin Islands <>
R. Strausbaugh (U. of the Virgin Islands), A. Cucchiara (College of Marin) report on behalf of a larger collaboration:

We observed Swift GRB 220117A (Melandri et al., GCN 31466) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on January 18, from 01:16 to 01:33 UT (corresponding to 6.97 to 7.25 hours from the GRB trigger time) with the Bessel R and I filters.

We performed a series of 3x320s exposures in I band and 1x152s in R band (the planned observations in R were interrupted). We detect the source at the XRT enhanced coordinates (Beardmore et al., GCN 31472) and VLT observations (Palmerio et al., GCN 31480) in I band, but not R band. The following magnitudes and upper limits are calculated using the USNO-B.1 catalog as reference:


These magnitudes are not corrected for galactic extinction.

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