{
  "bibcode": "2026GCN.45252....1M",
  "circularId": 45252,
  "eventId": "EP260727a",
  "createdOn": 1785329738317,
  "submittedHow": "email",
  "submitter": "Alexander Moskvitin at SAO RAS <mosk@sao.ru>",
  "body": "\nA. Moskvitin (SAO RAS), A. Pozanenko (IKI), N. Pankov (IKI)\nreport on behalf of GRB follow-up team\nWe observed the field of EP260727a (Hu et al., GCN 45235) \nwith the Zeiss-1000 1-m telescope of SAO RAS equipped \nwith the CCD photometer. We obtained 9*20 + 4*300 sec. images \nwith Rc filter from 2026-07-27T23:31:14 to 2026-07-28T00:07:51\nunder mediocre weather conditions and seeing of 3\".3.\nThe OT (He et al., GCN 45234; Eyles-Ferris et al., GCN 45239;\nAdami et al., GCN 45243; Guziy  et al., GCN 45245; also consistent \nwith the EP-FXT position, Wu et al., GCN 45244) is clearly detected \nin the stacked image with the following brightness.\nDate        UTstart  t-T0     Exp.   Filter Mag    Err.    UL\n                    (mid, h) (n*s)                      (3-sigma)\n                   \n2026-07-27  23:31:14  3.1932  1380   Rc     21.64 +/- 0.17  22.5    \nNear the position of the second candidate proposed by Adami et al., \n(GCN 45243) we note the presence of an extended source \nwith the coordinates (J2000.0) R. A. = 23:05:48.72; Dec. = +03:15:23.5\nand brightness of R = 21.55 +/- 0.11.\nThis preliminary photometry was given in the Vega system, calibrated \nagainst nearby SDSS stars (magnitudes converted with Lupton 2005 \nequations) and not corrected for Galactic extinction.\n",
  "subject": "EP260727a: SAO RAS optical observations"
}