{
  "eventId": "EP260227a",
  "createdOn": 1772261471840,
  "body": "S.Y. Fu (HUST), L.B. He, Z.P. Zhu, J. An, X. Liu, S.Q. Jiang, D. Xu (NAOC), J. P. U. Fynbo (DAWN/NBI), A. L. Bouquin (NOT) report on behalf of a large collaboration:\n\nWe observed the field of EP260227a (Wang et al., GCN 43869) using the 2.56-m Nordic Optical Telescope (NOT) equipped with the ALFOSC camera. The observations started at 02:20:46 UT, 2026-02-28, i.e. 6.14 hrs after the trigger, and we obtained 3x120 s frames each in Sloan g', r' and i' bands.\n\nThe previously reported optical counterpart (Eyles-Ferris et al., GCN 43867; Li et al., GCN 43868) was detected in our stacked frames with the following AB magnitudes:\n\n| t-mid (hrs) | filter |      mag     |\n| ----------- |--------| ------------ |\n|    6.21     |   g'   | 21.40 ± 0.20 |\n|    6.33     |   r'   | 21.50 ± 0.20 |\n|    6.46     |   i    | 21.37 ± 0.12 |\n\ncalibrated using nearby Pan-STARRS1 dr2 catalog, and not corrected for Galactic extinction.",
  "circularId": 43873,
  "submitter": "L. B. He at NAOC <helb@bao.ac.cn>",
  "submittedHow": "web",
  "subject": "EP260227a: NOT optical observations",
  "format": "text/markdown",
  "bibcode": "2026GCN.43873....1F"
}