Upload
chogan
View
37
Download
0
Embed Size (px)
DESCRIPTION
Michael Brown (NOAO->Princeton) Buell Jannuzi (NOAO) Arjun Dey (NOAO) Glenn Tiede (Bowling Green) Tod Lauer (NOAO) Alyson Ford (NOAO->Swinburne) Lissa Miller (NOAO->Yale) NDWFS Survey Team. The Clustering of Red Galaxies & EROs. MGCT, Baltimore, September 2004. - PowerPoint PPT Presentation
Citation preview
Michael Brown (NOAO->Princeton)Buell Jannuzi (NOAO)
Arjun Dey (NOAO)Glenn Tiede (Bowling Green)
Tod Lauer (NOAO)Alyson Ford (NOAO->Swinburne)
Lissa Miller (NOAO->Yale)NDWFS Survey Team
The Clustering of Red Galaxies & EROs
MGCT, Baltimore, September 2004
Imaging of 18 square degrees with KPNO & CTIO telescopes.
Limiting magnitudes of BW
~26.5, R~25.5, I~25.0, & K~19.0.
Comoving volume to z~5 is 0.3 Gpc3.
9 square degree BW
RIK imaging data release on October 22.
Imaging with Spitzer (IRAC+MIPS), Chandra, & GALEX.
4 to 10m spectroscopy including 10k Hectospec redshifts
Two preliminary clustering studies : Red Galaxies and EROs.
orDoes evolveinto ?
z~2 z~0 z~0
Kinematics of z>1 galaxies can have large uncertainties.
Stellar masses of z>1 galaxies are uncertain.
SED evolution of z>1 galaxies is uncertain.
Clu
ster
ing
Str
engt
h
Luminosity (BJ)
L* Bright
Redshift
Spatial clustering : Data and Models
Stars ~3x1010 MSun
Flux limited samples mix redshifts, SEDs and luminosities.
Galaxy clustering is a function of SED and luminosity at z~0.
Angular scale
Clu
ster
ing
stre
ngthw(1')=0.024g=1.81
Tracing galaxy evolution via clustering
Select galaxies as a function of restframe properties & epoch.
Imaging surveys can cover large volumes to great depth.
Requires accurate photometric redshifts.
Use clustering to identify galaxies in massive DM halos.
Connect galaxies populations as an evolutionary sequence.
However, does clustering evolve as predicted by the models?
How does clustering evolve?
Smail et al. (2003)
How does galaxy clustering evolve?
Select the same galaxy population as a function of redshift.
Select galaxies with comparatively slow SED evolution.
Select galaxies with accurate photometric redshifts.
Brown et al. (2003), ApJ, 597, 225.
5325 0.3<z<0.9 red galaxies from ~1 sq degree.
Selected subsamples by luminosity, redshift and SED.
Compared measured clustering with the models, 2dF & SDSS.
Red galaxy apparent colours
PEGASE ModelsNDWFS
LBGs
FBGs
Spectroscopic Redshift
Pho
tom
etri
c R
edsh
ift
Red galaxy BW
RI photometric zs
Angular clustering
Angular scale
~L*
Restframe BW
-R>1.44
Clu
ster
ing
stre
ngth
Redshift
Obj
ects
per
uni
t red
shif
t
Redshift distributions
Evolution corrected luminosity
Spa
tial
Clu
ster
ing
Red galaxies at 0.3<z<0.9
2dF
NDWFS
Redshift
Spa
tial
Clu
ster
ing
~L* red galaxies at 0.3<z<0.9
NDWFS
SDSS
2dF
Red galaxy clustering at 0.3<z<0.9
Brown et al. (2003), ApJ, 597, 225.
Spatial clustering is correlated with luminosity (mass).
Spatial clustering is weakly correlated with redshift.
Spatial clustering is consistent with hierarchical models.
The full survey area is required for robust tests of models.
Next NDWFS data release is on October 22.
R-K>5, z~1 Extremely Red Objects
Brown et al. (2004), ApJ, submitted.
EROs are presumed to be the progenitors of local ellipticals.
Dusty starbursts and galaxies with “old” stellar populations.
Extreme clustering? Possibly with r0>10 Mpc for <L*?
617 K<18.4 EROs selected from ~1 sq degree.
Largest ERO sample size by 2x. Largest ERO volume by 4x.
Extremely luminous galaxies, with L~3L*(z=0).
Angular Scale
Ang
ular
clu
ster
ing
Angular clustering
Spectroscopic Redshift
Pho
tom
etri
c R
edsh
ift
Extremely Red Objects
Redshift
Obj
ects
per
uni
t red
shif
t
Redshift distributions
Red galaxies and K<18.4 EROs
Redshift
Spa
tial
Clu
ster
ing
EROs3L* Red
2dF
SDSS
LCDM
K-band magnitude limit
Ang
ular
clu
ster
ing
at 1
'
Are <L* EROs strongly clustered?
Completed preliminary z<1.4 studies with ~1 sq degree.
Galaxy clustering is a function of luminosity and mass.
Galaxy clustering does not evolve rapidly with redshift.
Observed clustering is consistent with hierarchical models.
ERO clustering is strong, but not unusually strong.
Larger area will robustly test hierarchical models.
We will use galaxy clustering to measure galaxy evolution.
Next imaging data release is 22 October 2004.