TITLE: GCN CIRCULAR NUMBER: 33149 SUBJECT: GRB 221231A: 3.6m DOT optical upper limit DATE: 23/01/04 13:56:14 GMT FROM: Amit Kumar Ror at ARIES Amit K. Ror, Rahul Gupta, S. B. Pandey, A. Aryan, A. Ghosh, Dimple, and K. Misra (ARIES) report: We observed the field of GRB 221231A detected by Fermi/GBM (2022, GCN 33129) using the 3.6m Devasthal Optical Telescope of ARIES Nainital. We have taken multiple frames having an exposure time of 200 sec in the r filter. We stacked the images after the alignment. We did not find any evidence of an afterglow candidate inside the Swift XRT error circle (Perri et al. 2023, GCNs 33135 and 33139). We obtained the limiting mag of ~ 21.7 mag at ~ 1.87 days post-detection. The non-detection of the optical afterglow is consistent with Odeh 2023, GCN 32876. The limiting magnitudes quoted are not corrected for the Galactic and host extinction in the direction of the burst. Photometric calibration is performed using the standard stars from the Pan-STARRS catalog. This circular may be cited. 3.6m Devasthal Optical Telescope (DOT) is a recently commissioned facility in the Northern Himalayan region of India (long: 79 41 04E, lat: 29 21 40N, alt: 2540m) owned and operated by the Aryabhatta Research Institute of Observational Sciences (ARIES), Nainital ( https://www.aries.res.in). The authors of this GCN circular thankfully acknowledge the consistent support from the staff members to run and maintain the 3.6m DOT.