TITLE: GCN CIRCULAR NUMBER: 19022 SUBJECT: LIGO/Virgo GW150914: BOOTES-3 simultaneous imaging DATE: 16/02/18 22:51:31 GMT FROM: Alberto J. Castro-Tirado at IAA-CSIC A. J. Castro-Tirado (IAA-CSIC Granada & ISA-UMA Málaga), J. C. Tello, R. Cunniffe, S. R. Oates, B.-B. Zhang, S. Jeong (IAA-CSIC Granada), A. Castellón (Univ. of Málaga), M. Jelinek (ASU-CAS Ondrejov), N. Rattenbury and Ph. Yock (Univ. of Auckland) and R. Querel (NIWA, Lauder) report: A search of the CASANDRA-3 allsky camera database at the BOOTES-3 astronomical station in Lauder (New Zealand), reveals a series of 36s images taken during the night of the LIGO/Virgo alert, covering the entire southern sky error-box. In particular, amongst the hundreds of exposures, there is one starting at 09:50:22 UT that is contemporaneous to the LIGO/Virgo GW150914 event. Although a detailed investigation is ongoing, a limit of ~5th magnitude (due to poor weather conditions) is obtained for any optical transient within that error box. [GCN OPS NOTE(18feb16): Per author's request, RC was added to the author list.]