GRB 210704A: further TNG optical observations
Abstract
We carried out further observations of the optical afterglow of GRB 210704A (Kim et al. GCN Circ. 30384; D'Avanzo et al. GCN Circ. 30385) with the Italian 3.6m TNG telescope equipped with the optical camera DOLORES. A series of images were obtained with the i-sdss and r-sdss filters on 2021-07-08 from 21:22:44 UT to 22:36:58 UT (i.e. about 4.1 days after the burst) under non optimal seeing conditions (2"). A faint source, possibly extended, is detected at the optical afterglow position. With preliminary photometry we derive the following magnitudes: r = 23.35 +/- 0.16 i = 23.39 +/- 0.14 (AB; calibrated against the SDSS catalogue). Because of the seeing conditions and the source faintness we cannot definitely confirm if the source is extended or point-like. Further deep optical observations are encouraged to monitor the light curve evolution and to check if there is any contribution from an underlying host galaxy.
- Publication:
-
GRB Coordinates Network
- Pub Date:
- July 2021
- Bibcode:
- 2021GCN.30432....1D