GRB 210410A: RATIR Optical and NIR Observations
Abstract
We observed the field of GRB 210410A (Fermi GBM team, et al., GCN 29777) with the Reionization and Transients Infrared Camera (RATIR) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2021/04 10.30 to 2021/04 10.51 UTC (6.26 to 11.25 hours after the BAT trigger), obtaining a total of 2.16 hours exposure in the r and i bands and 0.87 hours exposure in the Z, Y, J, and H bands. We detect one source within the Swift-XRT error circle (Melandri, et al., GCN 29778). In comparison with the USNO-B1 and 2MASS catalogs, we find these magnitudes (in the AB system and not corrected for Galactic extinction in the direction of the GRB): r = 23.79 +/- 0.30 i = 22.49 +/- 0.14 Z = 22.07 +/- 0.27 Y = 21.14 +/- 0.18 J = 20.24 +/- 0.11 H = 20.17 +/- 0.15 The source is located at RA, Dec = 17:59:1.00, +45:21:44.6 (J2000, +/-0.5"), which is 2 arcsec away from the candidate optical afterglow position reported by Jelinek et al. (GCN 29780). It is possible that an astrometric cross-comparison could reveal our sources to be the same, in which case the optical afterglow continues to fade strongly. It is also possible that we are detecting the GRB host galaxy. A photo-z analysis suggests the redshift is z<3.6 (90% confidence). We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- April 2021
- Bibcode:
- 2021GCN.29784....1B