{
  "bibcode": "2018GCN.23020....1S",
  "body": "S. Schmalz (KIAM), F. Graziani (GAUSS). A. Pozanenko (IKI), A. Volnova \n(IKI),  E. Mazaeva  (IKI),  I. Molotov (KIAM) report on behalf of larger GRB \nfollow-up collaboration:\n\nWe observed the field of GRB 180720B (Swift-BAT detection: Siegel et al., \nGCN 22973, GCN 22975; Fermi-LAT detection: Bissaldi and Racusin, GCN 22980; \nFermi-GBM detection: Roberts et al., GCN 22981; MAXI/GSC detection: Negoro \net al., GCN 22993; Konus-Wind detection:  Frederiks et al., GCN 23011) \nwith  ORI-22 (22 cm) telescope of ISON-Castelgrande observatory starting on \nJuly 20  (UT) 23:04:30.  We obtained 150 images of 60 s exposure in Clear \nfilter.  The optical afterglow (e.g. Martone et al. GCN 22976;  Sasada et \nal., GCN 22977;  Reva et al., GCN 22979; Itoh et al., GCN 22983; Kann et \nal., GCN 22985)  is  detected in  separate images up to the end of series.\n\nThe coordinates of the optical afterglow are (J2000) \n:02:06.792   -02:55:04:99  with uncertainties of about 0.5 arcsec in both \ncoordinates.  Preliminary photometry  of the  afterglow at  (UT, mid time) \n23:22:21 is R =17.40 +/- 0.15. The photometry is  based on nearby USNO-B1.0 \n(R2) stars.",
  "circularId": 23020,
  "createdOn": 1532302749000,
  "email": "apozanen@iki.rssi.ru",
  "subject": "GRB 180720B:  ISON-Castelgrande optical observations",
  "submitter": "Alexei Pozanenko at IKI, Moscow  <apozanen@iki.rssi.ru>",
  "eventId": "GRB 180720B"
}