TITLE: GCN CIRCULAR NUMBER: 38253 SUBJECT: GRB 241115A: Mephisto upper limits DATE: 24/11/16 14:26:24 GMT FROM: Brajesh Kumar at SWIFAR, YNU Guowang Du, Brajesh Kumar, Weikang Lin, Yehao Cheng, Yaosong Yu, Yu Pan, Xingzhu Zou, Xinlei Chen, Jinghua Zhang, Yuanpei Yang, Yuan Fang, Xiangkun Liu, Xiaowei Liu (SWIFAR, YNU) report on behalf of the Mephisto Team: The field of GRB 241115A (Williams et al., GCN 38235)was observed with the 1.6m Multi-channel Photometric Survey Telescope (Mephisto) of Yunnan University located at Lijiang Observatory starting from 15:54:07 UT 2024-11-15 (~2.6 hr after the trigger). Multiple frames with 180s and 50s exposures in uvgr bands were taken. No new source is detected in our stacked images, consistent to Lipunov et al., (GCN 38237) and Strausbaugh & Cucchiara (GCN 38246). The 3-sigma upper limits are listed below. Start_Time(UT) Band Exp(s) Lim-mag(AB) 2024-11-15T15:54:07 u 180*3 >20.35 2024-11-15T16:04:30 v 180*3 >20.65 2024-11-15T15:54:07 g 50*9 >21.06 2024-11-15T16:04:31 r 50*9 >21.38 -------------------------------------------------------------------------- Mephisto (Multi-channel Photometric Survey Telescope) is a 1.6m wide-field multi-channel telescope, the first of its type in the world, capable of imaging the same field of view in three optical bands simultaneously. It provides real-time, high-quality colors of stellar objects. The on-site telescope assemblage and commissioning were carried out in September 2022. The first light in all three channels was achieved on 2023 December 21. --------------------------------------------------------------------------