{
  "submittedHow": "web",
  "body": "L. Moretti  and E. Pavoni (Leavitt Observatory), in a large collaboration with:\nM.G. Dainotti (National Astronomical Observatory of Japan), \nY. Niino (Tokyo University, Institute of Astronomy), \nK. Kalinowski (Aarhus University, Department of Physics and Astronomy),\nB. De Simone (Universita' degli Studi Di Salerno)\nreport: \n\nWe imaged the field of GRB 231111A (Lipunov et al., GCN 34980; Melandri  et al., GCN 34981; Jiang et al., GCN 34982; Lipunov et al., GCN 34983; Kumar et al., GCN 34984; Osborne et al., GCN 34991; Wen-Long Zhang et al., GCN 34993; Pankov et al., GCN 34994; Osborne et al., GCN 34995; Ruocco, GCN 34997; Li et al., GCN 35001) with the telescope of Leavitt Observatory, Italy. Member of: \n\nUAI/SSV - Unione Astrofili Italiani/sezione stelle variabili, GRB section.\nATA - Associazione Tuscolana di Astronomia.\n\nThe observations started 189 minutes after the BAT trigger, at 17:26:49 UT on 2023/11/11, with our RC telescope D=250 mm F/D=8.\n\nWeather conditions were medium, with light and variable cloud cover. \n\nWe co-added 15 images of 120 sec each, acquired from 17:26:49 to 18:20:58 UT. All images are R (Cousins) filtered, calibrated with master dark and master flat.\n\nWe confirm a fading afterglow in the error box of the astrometrically corrected position measured by Swift-XRT (GCN 34991), at the following coordinates +/- 2 arcsec:\n\nRA(J2000.0)  =  19h 20m 45.25s\nDEC(J2000.0) = +52d 26' 09.9''\n\nThe result of our photometry is:\n\n-------------------------------------------------------------------------\nJD_UTC at mid-exposure       mag            Err              Flt   \n-------------------------------------------------------------------------\n2460260.2464583                      20.1            +/- 0.2            R    \n    \n\nMagnitudes were estimated with the Gaia DR3 catalogue (*) and are not corrected for galactic dust extinction.\n\nThe message may be cited.\n\n(*) https://gea.esac.esa.int/archive/documentation/GEDR3/Data_processing/chap_cu5pho/cu5pho_sec_photSystem/cu5pho_ssec_photRelations.html",
  "eventId": "GRB 231111A",
  "circularId": 35003,
  "createdOn": 1699809360685,
  "subject": "GRB 231111A: Leavitt Observatory optical observations",
  "submitter": "leavittob@gmail.com",
  "bibcode": "2023GCN.35003....1M"
}