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[Fe/H]M 87 NGC 205 M 313 Aspects of Galaxy EvolutionM 32LMCSpectralBruzual '83ffSplendid manifold of local galaxies :? How & when did they form & how did they evolve ?2 approaches :? nature vs. . nurture ?☛ study distant galaxies : identify progenitorshigh redshift☛ study nearby galaxies in detail : traces of their historyastro-archeologyObservations = snapshotsEvolution of galaxies ↔ numerical modelsU. Fritze, HD Grad. Days 2008Tinsley '68ffChemicalObservational relationsDynamicalOriginally modelled one by one independently.Now attempting to couple consistently : GALEV models *S : formation & evolution of stars +/- gas +/- dustC : formation & nucleosynthesis of stars; infall/outflow of gasD : internal & external gravitation, stars + gas + DM* 2003 Hertha-Sponer Research award DPGToomre '72ffU. Fritze, HD Grad. Days 2008Local GalaxiesLocal GalaxiesFundamental relations for Ellipticals & dEs :Fundamental relations for Ellipticals & dEs :Color – magnitude relation : brighter Es are redderColor – magnitude relation : brighter Es are redder(de Vaucouleurs 61, 72, fffff)Luminosity – metallicity relation : brighter Es are moremetal-richFaber – Jackson relation : central velocity dispersionincreases with luminosity➔ distance determinationKormendy's relations :brighter Es have large effective radiibrighter Es have lower (average) surface brightness.Sphs (and GCs) do not follow Kormendy's relations.Fundamental Plane relations : effective radius – surfacebrightness – luminosity – central velocity dispersion➜ M/L increases with L U. Fritze, HD Grad. Days 2008 U. FritzeFritze, HD Grad. Days 2008Local GalaxiesFundamental relations for Ellipticals & dEs :Luminosity – metallicity relation : brighter Es are moremetal-rich*Vader 86,Bica & Alloin 87,Skillman 89U. Fritze, HD Grad. Days 2008Local Galaxies* how to measure stellar abundances/metallicities inellipticals/S0s/star clusters:from absorption lines !The stronger the absorption line of a given atom ormolecule in a stellar spectrum, the more of it must bein the stellar photosphere (c.f. ionization corrections,etc.).In integrated spectra of galaxies it’s s morecomplicated: luminosity weighted mean stellarabundances/metallicities~ 20 Lick indices, measured in extenso in stellarspectra with dependencies on [Fe/H]*, Teff andsurface gravity studied in detail (e.g. Mg2, Mgb, NaD,Fe52, …, TiO, …)U. Fritze, HD Grad. Days 200811