{
  "subject": "GRB 260909A: Xinglong 2.16m optical upper limit",
  "eventType": [
    "GRB"
  ],
  "format": "text/plain",
  "submitter": "Yinuo Ma <mayn@bao.ac.cn>",
  "eventId": "GRB 260909A",
  "body": "Y. N. Ma, L. J. Chen, L. P. Xin, Y. L. Qiu, C. Wu, J. Wang, X. H. Han, P. P. Zhang, H. L. Li, J. Wang, J. Zheng, J. Y. Wei (NAOC), C. Plasse (HKU), A. Li (BNU) report on behalf of SVOM follow-up team:\n\nWe observed the field of GRB 260909A triggered by SVOM/ECLAIRs (Saccardi et al., GCN 45534) using the 2.16m telescope located at Xinglong observatory, China, equipped with the BFOSC camera. We obtained 3*60s frames in R-band, starting at 13:09:25 UT on 2026-09-09, about 1.86 hours after the trigger.\n\nNo uncatalogued source was detected in our stacked images compared to the Pan-STARRS catalog within the error box provided by SVOM/MXT (Saccardi et al., GCN 45534) down to 3-sigma upper limit of about 20.6 mag.\n\nOur result is consistent with SVOM/C-GFT (Guan et al., GCN 45535).\n\nWe thank the staff at Xinglong observatory for their excellent support.",
  "circularId": 45536,
  "bibcode": "2026GCN.45536....1M",
  "createdOn": 1788969561701,
  "submittedHow": "web"
}