{
  "bibcode": "2016GCN.19483....1M",
  "body": "E. Mazaeva (IKI),  E. Klunko (ISTP), A. Volnova (IKI),   I. Korobtsev \n(ISTP),  A. Pozanenko (IKI) report on behalf of larger GRB follow-up \ncollaboration:\n\nWe observed the field of the Swift  GRB 160601A (Kocevski et al., GCN \n19478) with AZT-33IK telescope of Sayan observatory (Mondy)  starting on \nJune, 01 (UT) 15:00:41.  We obtained several images in R-filter under \ngood weather conditions and FWHM of 1.5 arcsec. Using only part of \nimages available we marginally detect (S/N ~2) a source at the edge of \nSwift-XRT position (Kocevski et al., GCN  19478).   Coordinates of the \nsource are (J2000) 15:39:44.43 +64:32:19.3 with uncertainty of 1 arcsec. \nPreliminary photometry  of  the source is R~22.3, and details of \nobservations are   following\n\nDate        UT start   t-T0    Filter  Exp.   OT(?)  UpperLimit (3 sigma)\n                       (mid, days)      (s)\n\n2016-06-01  15:00:41   0.03026  R      16*60  22.3   21.8\n\nPhotometry is based on nearby SDSS-DR9 stars, Lupton transformations into R:\nSDSS-DR9_id            R(Lupton)\nJ153959.67+643325.7    16.72\nJ153956.37+643102.2    17.00\nJ153931.88+643247.0    17.02\nJ153927.50+643304.3    19.23\nJ153942.70+643016.4    16.27\n\nWe will update the results after all the data will be available.",
  "circularId": 19483,
  "createdOn": 1464810848000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 160601A: Mondy optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 160601A"
}