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GCN Circular 30141

GRB 210606A: 1.5m OSN optical upper limit
2021-06-07T11:02:31Z (3 years ago)
Youdong HU at IAA-CSIC <>
T.-R. Sun, Y.-D. Hu, A. J. Castro-Tirado, V. Casanova, M. D. Caballero-Garcia, M. A. Castro Tirado and E. Fernandez-Garcia (IAA-CSIC), on behalf of a larger collaboration, report:

Following the detection of GRB 210606A by both Fermi (Fermi/GBM GCNC 30131) and Swift (DeLaunay et al. GCNC 30134), we triggered the 1.5m OSN telescope in Granada (Spain) starting on June 6 at 21:08 UT (i.e. ~17.2 h post burst) in order to cover the Swift/BAT error region. Images were taken in BVRI bands. No optical afterglow is detected in the error box down to R=22.2 in the combined (3x600s) image, which is in agreement with the non-detections reported by Lipunov et al. (GCNC 30132) and Pereyra et al. (GCNC 30135).

We thank the staff at OSN for their excellent support.
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