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GCN Circular 30367

GRB 210702A: BOOTES-3/YA optical counterpart observations
2021-07-04T11:59:24Z (3 years ago)
Youdong HU at IAA-CSIC <>
Y.-D. Hu, E. Fernandez-Garcia, T.-R. Sun, A. J. Castro-Tirado, M. D. Caballero-Garcia, M. A. Castro Tirado (IAA-CSIC), I. Carrasco and C. Perez del Pulgar (Univ. de Malaga), and R. Querel (NIWA), on behalf of a larger collaboration,

The 60cm BOOTES-3/YA robotic telescope at NIWA Lauder in Otago (New Zealand) automatically responded to the Swift trigger of GRB 210702A (Lien et al. GCNC 30351), which also detected by CALET (Yamaoka et al. GCNC 30362) and AGILE (Ursi et al. GCNC 30363), after the twilight as soon as possible. The first image (clear filter) were obtained starting at 07:00:58 UT (~11.9 hrs after trigger). At the enhanced Swift/XRT position(D'Elia et al. GCNC 30358), we found the optical counterpart reported by MASTER (Lipunov et al. GCNC 30352), MeerLICHT (Groot et al. GCNC 30354), Swift/UVOT (Lien et al. GCNC 30351, Kuin et al. GCNC 30355), VLT (Xu et al. GCNC 30357), iTelescope (Romanov GCNC 30364) and Chilescope (Belkin et al. GCNC 30365) with a magnitude of R = 18.0+-0.1 in the co-added image (10 x 60 s), which calibrated with nearby stars in USNO-B 1.0 catalog. Further analysis is ongoing.

We thank the staff at NIWA for its excellent support.
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