TITLE: GCN CIRCULAR NUMBER: 30848 SUBJECT: GRB 210919A: BOOTES-2/TELMA optical upper limit DATE: 21/09/19 01:57:54 GMT FROM: Youdong HU at IAA-CSIC <huyoudong072@hotmail.com> Y.-D. Hu, T.-R. Sun, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco (Univ. de Malaga), R. Fernandez-Munoz (IHSM/UMA-CSIC) and M. Jelinek (ASU-CAS), on behalf of a larger collaboration, report: The 60cm BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain) automatically responded to the Swift trigger of short GRB 210919A (Tohuvavohu et al. GCNC 30846). Images were taken starting at 00:32 UT on 19 Sep (~4 min after trigger) under high airmass conditions. In the co-added 10 x 10 s exposure image (clear filter), no optical afterglow is detected within the reported XRT/Swift source position (Tohuvavohu et al. GCNC 30846) down to 17.5 mag. This non-detection is consistent with reports from Tohuvavohu et al.(GCNC 30846) and Lipunov et al.(GCNC 30847). We thank the staff at La Mayora for its excellent support.