A near-IR low-resolution spectroscopic follow-up of a complete sample of K<18.5 EROs has started at the 3.5 m Telescopio Nazionale Galileo (TNG, La Palma, Canary Islands) by using a prism disperser AMICI. The sample has been selected from the Munich Near-I

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aToappearin“GalaxyEvolution:TheoryandObservations(2002)”RevMexAA(SC)TESIS-THETNGEROSSPECTROSCOPICIDENTIFICATIONSURVEYP.Saracco1,M.Longhetti1,P.Severgnini1,R.DellaCeca1,R.Bender2,N.Drory2,G.Feulner2,F.Ghinassi3,U.Hopp2,F.Mannucci4,C.Maraston2Theepochatwhichmassivegalaxies(Mstar>1011M⊙)haveassembledprovidescrucialcon-straintsonthecurrentgalaxyformationandevolutionmodels.TheLCDMhierarchicalmergingmodelpredictsthatmassivegalax-iesareassembledthroughmergersofpre-existingdiskgalaxiesatz≤1.5(Kau mann&Charlot1998;Coleetal.2000).Inthealter-nativeviewmassiveellipticalsformedatz>3inasingleepisodeofstarformationandfol-lowapureluminosityevolution(PLE).ThenumberdensityofMstar>1011M⊙galaxiespre-dictedintheLCDMmodelbyBaughetal.(2002)is～10 5h3Mpc 3atz 1.whichgivesanupperlimittothesurfacedensityofmassivegalaxiesof0.02gal/arcmin2intheredshiftrange1.2<z<1.5.Giventhislowpredictedprobability,searchingformassivegalaxiesatz≥1.2andestimatingtheirnumberdensityprovidestrongobservationalcon-straintsonmodels.Withtheaimatidentifyingmas-siveevolvedgalaxiesatz≥1.2,westartedanear-IRverylowresolutionspectroscopicsurveyofacom-pletesampleofK’<18.5EROs(R-K’>5).Indeed,K～18.5istheexpectedapparentK-bandmagnitudeofaMstar=1011M⊙galaxyatz～1.Thesample(15EROsatK’<18and52atK’<18.5)hasbeense-lectedfromtwono-adjacentwideareasofabout180arcmin2eachoftheMunichNear-IRClusterSurvey(MUNICS,Droryetal.2001).TheobservationsarebasedontheAmiciprismdispersingelementmountedatthenear-IRcameraNICSoftheTelesco-

pioNazionaleGalileo(TNG).Thisobservingmodeprovidesthespectrumfrom8500-24000 Ainoneshotwithanearlyconstantresolution(λ/ λ～50)andahighthroughput(～80%).ForthesereasonstheAmicidataresultverye cientinestimatingredshiftofoldstellarsystemsinthe1.2<z<2rangethroughthedetectionoftheBalmerbreak.Ontheotherhand,boththelowresolutionandthelowS/N(～3)achievableatthesemagnitudesmakethedetectionandtheestimateofabsorption/emission