GCN Circular 29687
Subject
GRB 210321A: Xinglong GWAC-F60A optical observation
Date
2021-03-22T03:41:33Z (4 years ago)
From
Liping Xin at NAOC, SVOM <xlp@nao.cas.cn>
L. P. Xin(NAOC), C. Gao(GXU), X. H. Han(NAOC), J. Y. Wei(NAOC),
J. Wang(GXU), G. W. LI(NAOC), L. H. Li(NAOC), C. Wu(NAOC),
X. G. Wang(GXU), E. W. Liang (GXU), Y. L. Qiu(NAOC), and J. S. Deng(NAOC) report:
We began to observe GRB 210321A (Dichiara et al. GCN
29677; Perri et al. GCN 29678; Siegel et al. GCN 29679; Butler et
al. GCN 29680; Heintz et al. GCN 29684; Ugarte Postigo et al., GCN 29685)
with Xinglong GWAC-F60A telescope, China, at 11:30:49 (UT),
21th. Mar. 2021, about 4.28 hours after the burst.
A series of R, I images were obtained.
The optical counterpart ( Siegel et al. GCN 29679; Butler et al. GCN 29680;
Heintz et al. GCN 29684; Ugarte Postigo et al., GCN 29685)
was clearly detected in the stacked R-band image
observed during 11:30:49 and 12:48:17 UT.
The brightness was estimated to be 18.98 +/-0.13 mag at the mean
time of 4.88 hours after the burst, calibrated to USNO B1.0 R2 mag,
This result is consistent with the previous report (Zhu et al., GCN 29530).