TITLE: GCN CIRCULAR NUMBER: 35952 SUBJECT: X-ray transient EP240315a/AT2024eju: TShAO (Zeiss-1000) observatory optical upper limit DATE: 24/03/18 14:52:47 GMT FROM: Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru> N. Pankov (HSE, IKI), I. Reva (FAI), A. Pozanenko (IKI), S. Belkin (IKI), A. Volnova (IKI) report on behalf of IKI GRB FuN: We observed the field of the X-ray transient EP240315a (Zhang et al., GCN 35931) till now also detected by Follow-up X-ray Telescope of Einstein Probe (Chen et al., GCN 35951). The optical counterpart AT2024eju discovered by ATLAS (Srivastav et al., GCN 35932, 35933) and observed in optic (Jiang et al., GCN 35935; Saccardi et al., GCN 35936; Rau GCN 35937; Chen GCN 35938; Leonini et al., GCN 35944; Pankov et al., GCN 35945) was observed with Zeiss-1000 telescope of Tien Shan Astronomical Observatory stating on 2024-03-17 (UT) 14:12:06 in R filter. We do not detect the optical counterpart. Preliminary photometry of the filed is following Date UT start t-T0 Filter Exp. OT Err. UL(3sigma) (mid, days) (s) 2024-03-17 14:12:06 1.77526 R 35*120 n/d n/d 22.3 The photometry is based on nearby USNO-B1.0 (R2) stars. View this GCN Circular online at https://gcn.nasa.gov/circulars/35952. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...