{
  "format": "text/plain",
  "bibcode": "2026GCN.44686....1B",
  "circularId": 44686,
  "submitter": "Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>",
  "eventId": "GRB 260511A",
  "body": "H. Ban, T. Kato, K. Hotta, Y. Kawakubo, M. Serino, T. Sakamoto (AGU)\n\nWe observed the field of GRB 260511A detected by\nthe Fermi/GBM (Fermi GBM Team, GCN Circ. 44529),\nthe SVOM/ECLAIRs (Godet et al., GCN Circ. 44532),\nthe NuSTAR CsI anti-coincidence shields (Waratkar et al., GCN Circ. 44555),\nthe Konus-Wind (Ridnaia et al., GCN Circ. 44585),\nthe Glowbug (Woolf et al., GCN Circ. 44586), and\nthe GRID (Li et al., GCN Circ. 44664)\nwith the iTelescope.Net (http://www.itelescope.net) T75 (ASAN250) telescope\nlocated at Rio Hurtado Valley, Chile.\n\nWe took 20 images of 60 sec exposures in the Red filter starting from \nMay 11 at 06:37:27 (UT), about 24 minutes after the Fermi/GBM trigger \nand stopped at 07:07:42.\n\nThe afterglow (Jiang et al., GCN Circ. 44533; Akl et al., GCN Circ. 44534;\nSaccardi et al., GCN Circ. 44535; Zheng et al., GCN Circ. 44536;\nWu et al., GCN Circ. 44538; Harper et al., GCN Circ. 44545; \nBrivio et al., GCN Circ. 44562; Li et al., GCN Circ. 44575; \nFu et al., GCN Circ. 44579; Zhu et al., GCN Circ. 44584) is detected\nin the stacked image of the first eight images (total exposure of 480 s) \ncollected between 06:37:27 and 06:49:12. The afterglow magnitude is \n19.3 +- 0.6 using the USNO-B1 catalog. No afterglow was detected in \nthe following twelve images collected between 06:49:44 and 07:07:42.\nThe 5-sigma upper limit of the stacked image of the last twelve images \n(total exposure of 720 s) is 18.3 mag.",
  "createdOn": 1779404139645,
  "subject": "GRB 260511A: iTelescope T-75 optical detection",
  "submittedHow": "web"
}