Cosmic Evolution Survey (COSMOS)

HST I-band image 2 deg.2 ! ==> VLT-VIMOS, XMM, Subaru, VLA, Spitzer, Galex, …spectroscopy : VLT, Magellan, …

• overview • major multi-λ data• large scale structures • galaxy evolution vs z and environment

In early universe,

merging and interactions drive evolution !!

COSMOS survey ==> large-scale structure context

obs. argument :

<dist>L* (at z = 0) = 7 Mpc

==> 7' (z=1) , 4' (z=3) ==> 1 L*

for ~1000 gal. ==> ~ 1 deg

How big an area :

redshift slice from Λ CDM sim.

Coupled evolution of LSS, galaxies, star formation, AGN w/ Z

90 Mpc

COSMOS -- 38 ==> 80 team members -- US, Japan, Europe and Canada

Telescopes :

Hubble -- very fine & sensitive optical images XMM -- xray imaging Galex -- ultraviolet imaging Spitzer -- Mid IR w/ IRAC

Subaru -- multiple color imaging VeryLargeArray -- radio imaging ESO-VLT & Magellan-- opt. spec. ~ 45,000 gal. NIR -- NOAO, UH88, UKIRT …

Roberto AbrahamMasaru AjikiJustin AlpertHerve AusselJosh BarnesAndrew BlainDaniela CalzettiPeter CapakJohn CarlstromChris CarilliAndrea CimattiAndrea ComastriMarcella CorolloEmannuel DaddiRichard EllisMartin ElvisAmr El ZantShawn EwaldMike FallAlexis FinoguenovAlberto FranceschiniMauro Giavalisco

Richard GriffithsGigi GuzzoGunther HasingerOlivier IlbertChris ImpeyKnud JahnkeJean-Paul KneibKarel NelJeyhan KartaltepeJin KodaAnton KoekemoerLisa KewleyAlexie LeauthaudOlivier LeFevreIngo LehmannSimon LillyCharles LiuRichard MasseyHenry McCrackenYannick MellierSatoshi MiyazakiBahram MobasherTakashi MurayamaColin Norman

COSMOS -- Ludovic Van WaerbekePaolo VettolaniSimon WhiteLin YanMin Yun

Alexandre RefregierAlvio RenziniJason RhodesMike RichDimitra RigopoulouMara SalvatoDave SandersShunji SasakiDave SchminovichEva SchinnererNick ScovilleMarco ScodeggioKartik ShethPatrick ShopbellVernesa SmolcicJason SuraceYoshi TaniguchiJames TaylorDave ThompsonNeil TysonMeg UrryLudovic Van Waerbeke

LSS w/Capak, Finoguenov,Giavalisco, Guzzo,Mobasher, Sanders,Aussel, Salvato …

Major features :

• large area -- 1.4 x 1.4 deg => cover largest large scale structures • high sensitivity => morphology of L* galaxies at z < 2

• sensitivity + area => 2x106 galaxies ==> like SDSS at z > 0.5 • equatorial => multi-λ obs. from all tel.

COSMOS multi-λ

ACS 590 orbits

NICMOS-31.6 µm -- 24mag~7% of area

1.4deg

NICMOS-31.6 µm -- 25mag~7% of area

Cycle 12 & 13

Enormous area and sensitivity ==> large samples of all objects :

ACS source counts

completeness

COSMOS Photo-z catalog (Subaru, CFHT, NOAO)

Redshift distribution

Redshift uncertainties

LSS from galaxy overdensities in redshift slices ==>

Structures/Cluster identification :

• adaptive smoothing

avoid a priori assumptions

w.r.t. shapes and sizes

2 possibilities :

select all types of gal. or

just early (red seq.) types (easier)

but

precludes investigation of environmental effects

Test of adaptive smoothing:

~ 50% of gal. w/i structures~ 50% in field

overdensity galaxies

recovered distribution

• recovers all significant structures

• retains power on all scales

• no spurious recoveries

• conserves number counts

Σgal

w/ieach LSS

~ 42 large-scalestructures at z < 1.2

phot-z ==>

SED type ==> ages of stellar pop. vs environent

stellar mass , MV ==> buidup of massive gal. in LSS

SED + MV ==> star formation rates (SFR) as fn. of z and LSS

luminous early-type ==> dense core of LSS

phot-z ==> SED type , stellar mass , MV

M* = 3x1013 Msun !

LSS mass : Σ Mgalaxies w/i each LSS

photometric/luminous mass(DM halo ~ 50+ times larger) Richness class 2 -- 4

Mass in LSS as fn. of z

1012 - 1013Msunas expected w/ z

1013 - 1014Msuncounting stat.

XMM-Newton COSMOS

Hasinger etal

z =0.73 cluster : talks by Massey & Finoguenov

higher z ==> later type SED cores of LSS/halos ==> earlier type SED

Z

Gal

axy

type

Early (S0 & E)

Late (spirals and SB)

correlation of SED type w/ morphology

E/S0 Starburst

R1/4

flat

==>general correl. but …large dispersion

COSMOS structures probe Dark Matterpredictions of ΛCDM simulations :

1) mass distrib. of halos

2) galaxy occupation vs halo mass/size

3) relative areas / volumes as fn. of density

as fn. of z

area filling as fn. of density and z ==>

comparison w/ ΛCDM :

Z = 0Z = 1

obs.

Area filling factorin redshift slices

All LSS projected on line of sight :

Major aspects of COSMOS coming together :• HST , Subaru / CFHT / UKIRT / NOAO imaging complete photometry catalogs w/ ~ 1-2 million objects (26 mag) photo-z’s for 800,000 obj. (26 mag)• XMM , GALEX, Spitzer complete / ongoing• spectroscopy -- VLT, Magellan, Keck ongoing

see/ define large scale structures scales up to 10 - 20 Mpc -- M* = 1012 -- 1013 Msun

LSS ==> environmental effects on galaxy pop. & morph.

LSS properties consistent w/ predicted : mass spectrum area filling

more on High-z COSMOS in other talks