{
  "subject": "GRB 250706A: SAO RAS optical observations",
  "circularId": 41000,
  "submittedHow": "web",
  "bibcode": "2025GCN.41000....1M",
  "eventId": "GRB 250706A",
  "submitter": "Alexander Moskvitin at SAO RAS <mosk@sao.ru>",
  "createdOn": 1751860647641,
  "body": "A. Moskvitin and O. Spiridonova (SAO RAS),  \nreport on behalf of a GRB follow-up collaboration.\n\nWe observed the field of the GRB 250706A (Moss et al., GCN 40988)\nwith SAO RAS 1-m telescope Zeiss-1000 equipped with CCD-photometer. \nWe obtained 20 x 300 sec. images in Rc band on July 6, \n20:04:37--22:41:35 UT (t_mid - T0 = 5.5764 hours) under a good weather \nconditions and the seeing of 1\".6.\n\nIn the XRT error circle (Moss et al., GCN 40988) we detected a bright \nstellar-like source with the coordinates R.A. = 18:56:04.3, \nDec. = +32:19:13.5 (J2000.0) also presented in the archival images.\n\nAfter the PSF subtraction of this bright star we did not detect any \nsignificant sources down to the limiting magnitude of R_lim = 23.0.\n(based on the nearby USNO-B1.0 stars and not corrected \nfor the Galactic extinction)\n\nAdditionaly we divided whole set into two 10 x 300 sec. subsets\n(1st: t_mid - T0 = 4.9217 hours, 2nd: t_mid - T0 = 6.2393 hours)\nand found no significant residuals between two stacked images\nand no variability of the mentioned bright star within 0.01 mag.\nbetween two epochs.\n\nThis results are in agreement with OT non-detection by Moss et al. \n(GCN 40988); Mohan et al. (GCN 40990) and Wu et al. (GCN 40998).",
  "format": "text/plain"
}