Cosmic Evolution Survey (COSMOS) HST I-band image 2...
Transcript of Cosmic Evolution Survey (COSMOS) HST I-band image 2...
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