TITLE: GCN CIRCULAR NUMBER: 44442 SUBJECT: GRB EP260502a: BOOTES-7: early optical upper limit DATE: 26/05/02 09:00:37 GMT FROM: I. Perez-Garcia at Instituto de Astrofísica de Andalucía <ipg@iaa.es> I. Perez-Garcia, S.-Y. Wu, E. Fernandez-Garcia, M. D. Caballero-Garcia, R. Sanchez-Ramirez, S. Guziy, M. Gritsevich and A. J. Castro-Tirado (IAA-CSIC, Granada), C. Perez del Pulgar, A. Castellon, A. Reina (Univ. de Malaga),Y.-D. Hu (GXU), L. Hernandez-Garcia (Univ. de Valparaiso), D. R. Xiong (Yunnan Observatories of CAS), B.-B. Zhang (Nanjing Univ.) and A. Maury (Space, San Pedro de Atacama), on behalf of a larger collaboration, report: Following the detection of the fast X-ray transient EP260502a by the Einstein Probe (Liu et al., GCN 44440), the 0.6m BOOTES-7 robotic telescope at San Pedro de Atacama (Chile) observed the fast X-ray transient location starting on May 2, 06:23:31 UT (~14.7 min after trigger) in different optical bands. No new optical source is detected within the EP/WXT 3 arcmin error circle on the initial 10s image or on the first co-added clear-filter images (mid exposure time 2026-05-02 07:34 UT) down to 15.3 mag or 18.3 mag respectively, in agreement with the LCO upper limit (Li et al. GCN 44441). We thank the staff at San Pedro de Atacama Celestial Explorations observatory for their excellent support. View this GCN Circular online at https://gcn.nasa.gov/circulars/44442. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...