{
  "bibcode": "2019GCN.26483....1R",
  "body": "A. Rossi, M. Dadina, E. Maiorano, R. Gualandi (INAF-OAS), P. D'Avanzo, A. Melandri (INAF-OABr), M.T. Botticella (INAF-OAC), and E. Brocato (INAF-Abruzzo) report on behalf of GRAWITA\n\nWe observed the inner part of the error box obtained by the HAWC collaboration (Martinez-Castellano GCN #26472) during the follow-up of the GW trigger S191216ap (GCN #26454) with the 152cm Cassini Telescope at Loiano Observatory. The pointing was performed using the R filter. Four 10min exposures have been obtained starting at 18:12:29 on 2019-12-17 (UT), covering a mosaic of ~20'x20'. The observation was affected by bad seeing (4\"), low elevation, and passing clouds.\n\nIn preliminary analysis, assuming R=14.4 for the star at coordinates RA,DEC(J2000) 21:33:59, +05:16:21.5), for the galaxy #1 reported by Singer et al (GCN #26479) we measure R=16.6+-0.1. This is consistent with r=16.5 reported in SDSS catalog, within the photometric system and filter differences.\n\nNo other obvious candidate is visible down to R=18.5 mag and in comparison to DSS2 survey.\n\n���Sent from BlueMail ���",
  "circularId": 26483,
  "createdOn": 1576665864000,
  "email": "andrea.rossi@inaf.it",
  "subject": "LIGO/Virgo S191216ap: GRAWITA Loiano observations of HAWC error region",
  "submitter": "Andrea Rossi at INAF  <andrea.rossi@inaf.it>",
  "eventId": "LIGO/Virgo S191216ap"
}