Rojas, A. F.A. F.RojasMASETTI, NICOLANICOLAMASETTI0000-0001-9487-7740Minniti, D.D.MinnitiJiménez-Bailón, E.E.Jiménez-BailónChavushyan, V.V.ChavushyanHau, G.G.HauMcBride, V. A.V. A.McBrideBassani, L.L.Bassani0000-0003-4858-6963Bazzano, A.A.Bazzano0000-0002-2017-4396Bird, A. J.A. J.BirdGalaz, G.G.GalazGavignaud, I.I.GavignaudLandi, R.R.LandiMALIZIA, ANGELAANGELAMALIZIA0000-0002-6558-1163Morelli, L.L.MorelliPALAZZI, ELIANAELIANAPALAZZI0000-0002-8691-7666Patiño-álvarez, V.V.Patiño-álvarezSTEPHEN, JOHN BUCHANJOHN BUCHANSTEPHEN0000-0002-6017-0592Ubertini, P.P.Ubertini2020-09-072020-09-0720171405-2059http://hdl.handle.net/20.500.12386/27159We present the nature of 50 unidentified hard X-ray emitting objects detected with Swift-BAT and listed as of unidentified nature in the 54-month Palermo BAT catalogue. We found 45 extragalactic sources: 26 type 1 AGN, 15 type 2 AGN, one type 1 QSO, one starburst galaxy, one X-ray bright optically normal galaxy, and one LINER. We report 30 new redshift measurements, 13 confirmations and 2 more accurate redshift values. The remaining five objects are galactic sources: three are Cataclismic Variables, one is a X-ray Binary, and one is an active star.ELETTRONICOenConference posterhttps://www.iau.org/science/meetings/past/regional/1153/2017RMxAC..49..153RFIS/05 - ASTRONOMIA E ASTROFISICA