Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to https://gcn.nasa.gov.
New! Circulars over Kafka, Heartbeat Topic, and Schema v4.1.0. See news and announcements

GCN Circular 30770

Subject
GRB 210905A: Continued LCO Optical Observations
Date
2021-09-05T04:33:24Z (3 years ago)
From
Robert Strausbaugh at U. of the Virgin Islands <robert.strausbaugh@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 210905A (Sonbas, et al., GCN 30765) with the LCO 1-m Sinistro instrument at the Cerro Tololo Interamerican Observatory, Chile site, on September 5, from 02:32 to 02:53 UT (corresponding to 2.37 to 2.72 hours from the GRB trigger time) with the Bessel I filter.

We performed a series of 5x300s exposures in I band. We detect the same uncataloged source (Strausbaugh, et al., GCN 30769) at the following coordinates (309.0481637, -44.4402618).  Using the USNO-B.1 catalog as reference, we calculate the following magnitude:

I=20.4+/-0.1

These magnitudes are not corrected for galactic extinction.  There is clear evidence of fading from the first epoch (I=19.52+/-0.09) providing strong evidence that this is the afterglow of this burst.

R.S. is funded by NSF AST grant #1831682
Looking for U.S. government information and services? Visit USA.gov