{
  "eventId": "GRB 260809A",
  "submittedHow": "web",
  "format": "text/plain",
  "body": "L. Izzo (INAF/OACN and DARK/NBI), A. Saccardi (CEA/Irfu), G. Corcoran (UCD), report on behalf of a larger collaboration:\n\nWe observed the field of GRB 260809A detected by SVOM/ECLAIRs (Brunet et al., GCN  45331), using the ALFOSC camera mounted on the Nordic Optical Telescope (NOT). We obtained 3x300 s exposures in the SDSS r-band and 5x200s in the SDSS z-band.\n\nIn the stacked images, we detect the optical afterglow (Li et al., GCN 45336; Adami et al., GCN 45338; Rajabov et al., GCN 45339). We measure the following magnitudes calibrated against the Pan-STARRS catalog, and not corrected for Galactic extinction:\n\nr = 23.78+/-0.18, midtime: 2026-08-10 at 04:29:51 UT (13.54 hr post trigger)\nz = 22.25+/-0.13, midtime: 2026-08-10 at 04:47:47 UT (13.84 hr post trigger).",
  "createdOn": 1786349479857,
  "circularId": 45340,
  "subject": "GRB 260809A: NOT optical observations",
  "submitter": "Andrea Saccardi at CEA/Irfu <andrea.saccardi@cea.fr>",
  "bibcode": "2026GCN.45340....1I",
  "eventType": [
    "GRB",
    "Optical Transient"
  ]
}