GRB 220701A: MITSuME Akeno optical upper limits
Abstract
We observed the field of GRB 220701A (P. A. Evans et al. GCN Circular #32306 & #32308, B. O'Connor et al. GCN Circular #32309, S. R. Oates et al. GCN Circular #32310, Y.-D. Hu et al. GCN Circular #32311, R. Strausbaugh et al. GCN Circular #32313, J. D. Gropp et al. GCN Circular #32314, WeiKang Zheng et al. GCN Circular #32315, S. Belkin et al. GCN Circular #32317, Alan M. Watson et al. GCN Circular #32318) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm telescope Akeno. The observation with a series of 60 sec exposures started at 2022-07-01 19:37:09 UT (884 minutes after the Swift/BAT trigger). We stacked the images with good conditions. We did not detect any uncatalogued sources within the enhanced Swift/BAT error region (Evans et al. GCN Circular #32306). We obtained the 5-sigma limits of the stacked images as follows. T0+[days] | MID-UT | T-EXP[sec] | 5-sigma limits ------------------------------------------------------------------------------------------------ 0.6 | 2022-07-01 14:31:19 | 9060 | g'>19.4, Rc>20.1, Ic>20.9 ------------------------------------------------------------------------------------------------ T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used PS1 catalog for flux calibration. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ, Vol.73, Issue 1, Pages 4-24; https://github.com/MNiwano/Eclaire).
- Publication:
-
GRB Coordinates Network
- Pub Date:
- July 2022
- Bibcode:
- 2022GCN.32320....1T