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GCN Circular 27378

SGR Swift J1818.0-1607: BOOTES-4/MET optical limit
2020-03-13T05:26:09Z (4 years ago)
Alberto J. Castro-Tirado at IAA-CSIC <>
Y.-D. Hu, E. Fernandez-Garcia, A. J. Castro-Tirado (IAA-CSIC), C. Perez 
del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga),�� S. Guziy 
(Univ. of Nikolaev) and D. Xiong, Y. Fan, X. Zhao, J. Bai, C. Wang, Y. 
Xin (Yunnan Observatories of CAS), on behalf of a larger 
collaboration, report:

Following the detection of SGR Swift J1818.0-1607 by Swift (Evans et al. 
GCNC 27373), the 0.6m BOOTES-4/MET robotic telescope at Lijiang 
Astronomical Observatory (China) gathered images starting at 21:17:34 UT 
(47 s after trigger). No optical afterglow is found down to 19.3 mag (in 
co-added 10x10 s unfiltered images) within the Swift/XRT error box, 
consistent with the non-detection by Swift/UVOT (Evans et al. GCNC 
27373). Further observations are ongoing.

[GCN OPS NOTE(14mar20): Per author's request, Y.Xin's affiliation was changed
from "Yunnan Nacional Astronomical Observatory" to "Yunnan Observatories of CAS".]
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