TITLE: GCN CIRCULAR NUMBER: 42969 SUBJECT: EP251130a: MAO/AZT-22 optical observations DATE: 25/12/03 12:42:19 GMT FROM: Yodgor Rajabov at UBAI <rajabov@astrin.uz> B.Abidkhanov, Y. Rajabov, O. Burkhonov, S. Ehgamberdiev, Y. Tillayev (UBAI), T. Boyqobilov, A. Shaymanov (Maidanak Observatory/UBAI) report on behalf of UBAI team. We observed the field of EP transient EP251130a (Wu et al., GCN 42903 Zhang et al., GCN 42915), also detected by Swift/XRT (Evans et al., GCN 42908), with the AZT-22 1.5m telescope of the Maidanak Observatory (MAO) starting on 2025-12-01 at 20:31:41 UT. In total we obtained 6x300 s exposures in the R-band using 4kx4k CCD SNUCAM camera (Im et al., 2010). The optical counterpart (Dornic et al., GCN 42904; He et al. GCN 42914; Gupta et al. GCN 42916; Zheng et al. GCN 42917; van Dalen et al., GCN 42918; Moskvitin and Spiridonova, GCN 42919; Aryan et al., GCN 42921; Volnova et al., GCN 42922; Ma et al., GCN 42940; Corcoran et al., GCN 42951; and Rodríguez et. al., GCN 42963) is detected in the stacked frame. Preliminary photometry is the following: Date UTstart Exptime t-T0 Filter OT Err. UL Site/Telescope (nxs) (mid, days) 2025-12-01 20:47:55 6x300 1.40284 R 21.25 0.07 22.59 MAO/AZT-22 van Dalen et al. (GCN Circ. 42918) have reported a redshift of z = 4.035 using GTC OSIRIS+. All the data have been reduced by a single data processing pipeline, STDPipe (Karpov et al., 2022). Images obtained in Johnson Cousins filters were calibrated using the Gaia DR3 Synphot catalog. The data has not corrected for the Galactic extinction. Maidanak astronomical observatory (MAO) is an observational facility of the Ulugh Beg Astronomical Institute (UBAI), Uzbekistan Academy of Sciences (http://maidanak.uz/). View this GCN Circular online at https://gcn.nasa.gov/circulars/42969. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...