TITLE: GCN CIRCULAR NUMBER: 16299 SUBJECT: GRB 140518A: KAIT optical candidate DATE: 14/05/18 10:17:13 GMT FROM: Weikang Zheng at UC Berkeley WeiKang Zheng, Alexei V. Filippenko, Adam Morgan (UC Berkeley), and S. B. Cenko (NASA/Goddard Space Flight Center) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to GRB 140518A (Swift trigger 599287; Melandri et al., GCN 16298) starting at 09:22:16 UT, 270 s after the burst. Observations were performed with an automatic sequence in the clear (roughly R), V and I filters, and the exposure time was 20 s per image. We detect a faint object within XRT error circle at J2000 coordinates of: RA = 15:09:00.62 DEC= +42:25:05.9 with uncertainty of about 1". The object was only detected in the first clear band single image with mag R~18.3, no detection in following single images. But it is marginally detected in the co-add of next 5 single images with mag R~19.0. We suggest this to be the afterglow of the GRB. All mags are calibrated to USNO B1.0 catalog. [GCN OPS NOTE(18may14): Per author's request, the Subject-line was corrected from "140418A" to "140518A".]