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Click to edit the title text format,Click to edit the outline text format,Second Outline Level,Third Outline Level,Fourth Outline Level,Fifth Outline Level,Sixth Outline Level,Seventh Outline Level,Eighth Outline Level,Ninth Outline Level,Searching for massive galaxy progenitors,with,GMASS,(,G,alaxy,M,ass,A,ssembly,ultradeep,S,pectroscopic,S,urvey),(a progress report),Andrea Cimatti (INAF-Arcetri),M. Bolzonella (INAF-Bologna), P. Cassata (INAF-Milano), E. Daddi (NOAO), M. Dickinson (NOAO), A. Franceschini (Uni-Padova), C. Halliday (INAF-Arcetri), J. Kurk (MPIA), C. Mancini (Uni-Firenze), M. Mignoli (INAF-Bologna), L. Pozzetti (INAF-Bologna),A. Renzini,(INAF-Padova), G. Rodighiero (Uni-Padova), P. Rosati (ESO), G. Zamorani (INAF-Bologna),z, 0 0 z 1,1 z 1.5-2,z 1-2,GMASS,?,Search for the highest redshift ETGs,Identify and study the progenitors of massive ETGs,Stellar mass,assembly,evolution,at 1.5z3,GMASS main features,ESO VLT + FORS2 Large Program (145h; PI Cimatti),Target field :,50 arcmin,2,in the GOODS-South/HUDF region,Sample selection :,Spitzer+IRAC,m(4.5,m) 1.4,Sample size :,N(m1.4)= 390 , 210 in 6 spectroscopic masks,Ultradeep spectroscopy,to B=27, I=26,11h-30h,integration,Complementary to other surveys (depth, no color selections),100% of data taken in service mode up to 31 December 2005 (80% reduced),Reduced and calibrated data will be publicly available worldwide,Spitzer,VLT,Arcetri,GMASS target field,51 arcmin,2,within the,GOODS-South field,covering a large fraction,of the K20 and,Hubble Ultra Deep Field,(UDF) areas,Why 4.5,m selection ?,Best compromise among IRAC bands (sensitivity, PSF, IQ, blending),“Negative” k-correction (the stellar SED peak enters the 4.5,m-band for z1.5),Better sensitivity to stellar mass up to z,3,Less affected by dust extinction than K-band,1.6,m,bump,Preliminary redshift statistics,Small contamination from objects,with,zphot 1.4 and zspec 1.4,z(phot) or z(spec),z(spec) (literature + GMASS),z(spec) (GMASS only),Spectroscopic redshift efficiency:,red (12h-30h):,70% (not final),blue (11h-15h):,95%,Comparison with DRG selection,Spectra,J. Kurk,Average spectrum of first blue mask objects,N=35,M. Mignoli,Multi-band SEDs,Photometric SED fitting with,known,z(spec),UBVRIz + BViz + JH + JHKs + IRAC,Bolzonella, Pozzetti,Stellar mass estimates,zspec,zphot,Main properties, Passive or weakly star-forming,Old stars (1-3 Gyr),Massive (log M_stars = 10.9 11.2 Msun, Chabrier IMF),Low levels of specific SFR,Early-type morphology,Star-forming,Low mass blue systems (log M_stars, 10 Msun),Red systems with large mass (log M_stars 11+),and strong star formation (50-100 Msun/yr),Red more because of age than dust extinction,High specific star formation,Solar,metallicity,from UV,photospheric,features (,Halliday,et al.),Strong morphological K-correction,Star formation located mostly in outer regions,“Transition” phase leading to an old/massive ETG ?,Beyond GMASS ,Optical blank-fields + extremely K-band faint (KAB SFR1000 M_sun/yr,Post-starbursts z6.5 ?,Masses: 1011-1012,+,AGN,(Mobasher et al. 2006),Superantennae +Av=3,Dusty Torus,Mid-Infrared colours:,the bulk of the sources are consistent with a population of starbursts at z2-3,Are we looking at a,mixed population ?,Short summary,GMASS is designed to investigate the physical mechanisms leading,to the formation and mass assembly of massive early-type galaxies,In the redshift range of 1.5 z 6 or extreme dusty starbursts ?,Have a look at Claire Hallidays and Jaron Kurks posters,and,STAY TUNED !,
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