GRB 221027B: COATLI Upper Limits
Abstract
We observed the field of the GRB 221027B (Lien et al., GCN Circ. 32867) with the COATLI 50-cm telescope and HUITZI f/8 imager at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir ( http://coatli.astroscu.unam.mx) from 2022-10-28 01:47 UTC to 02:13 UTC (6.6 hours after the trigger), obtaining a total of 750 seconds of exposure in the r filter. We do not detect any uncataloged sources within the XRT error region (Beardmore et al., GCN Circ. 32868) to a 3-sigma limit of r > 21.4 mag. Our photometry is calibrated against the Pan-STARRS1 catalog, is on an approximate AB system, and is not corrected for Galactic extinction in the direction of the GRB. We thank the COATLI/HUITZI technical team and the staff of the Observatorio Astronómico Nacional.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- October 2022
- Bibcode:
- 2022GCN.32880....1B