Clustering Properties of Clustering Properties of Star Forming - - PowerPoint PPT Presentation

▶
clustering properties of clustering properties of star
SMART_READER_LITE
LIVE PREVIEW

Clustering Properties of Clustering Properties of Star Forming - - PowerPoint PPT Presentation

Sep 19, 2023 272 likes •416 views

Clustering Properties of Clustering Properties of Star Forming Galaxies at z ~ 2 Star Forming Galaxies at z ~ 2 BzK BzK z 2

slide-1
SLIDE 1

2007/1/30 2007/1/30

Clustering Properties of Clustering Properties of Star Forming Galaxies at z ~ 2 Star Forming Galaxies at z ~ 2

BzK BzK銀河のクラスタリングから探る 銀河のクラスタリングから探る z z～ ～2 2の星形成銀河の形成と進化 の星形成銀河の形成と進化

Masao Hayashi Masao Hayashi

(Univ. of Tokyo) (Univ. of Tokyo) collaborators collaborators K.

  • K. Shimasaku

Shimasaku、 、 K.

  • K. Motohara

Motohara、 、 M. Yoshida

  • M. Yoshida、

、

  • S. Okamura (Univ. of Tokyo)
  • S. Okamura (Univ. of Tokyo)、

、N.

  • N. Kashikawa

Kashikawa（ （NAOJ NAOJ） ）

slide-2
SLIDE 2

The universe at z~2 The universe at z~2

  • Galaxy formation and evolution based on the CDM model

Galaxy formation and evolution based on the CDM model

  • strong dependence on mass of dark

strong dependence on mass of dark-

  • halo (DH) (Mo & White 2002)

halo (DH) (Mo & White 2002)

  • The era of

The era of z~ z~2 2 Drastic changes occurred in the galaxy population at z~2 Drastic changes occurred in the galaxy population at z~2

  • The cosmic SFR and the number density of QSO have a peak at z~2

The cosmic SFR and the number density of QSO have a peak at z~2 (e.g., Dickinson et al. 2003; Richards et al. 2006) (e.g., Dickinson et al. 2003; Richards et al. 2006)

  • A significant evolution of the Hubble sequence occurred at z=1

A significant evolution of the Hubble sequence occurred at z=1-

  • 2

2 ( (Kajisawa Kajisawa & Yamada 2001; & Yamada 2001; Conselice Conselice et al. 2005) et al. 2005)

  • Galaxies at z~2

Galaxies at z~2 （ （redshift redshift desert desert） ）

  • BzK

BzK color selection color selection ⇒ ⇒ BzK BzK galaxies galaxies ( (Daddi Daddi et al. 2004) et al. 2004)

  • The only selection method of galaxies at z~2,

The only selection method of galaxies at z~2, irrespective of the amount of dust extinction irrespective of the amount of dust extinction

The Mass of dark The Mass of dark-

  • haloes hosting galaxies at z~2 is

haloes hosting galaxies at z~2 is inferred from clustering strength. inferred from clustering strength.

slide-3
SLIDE 3

BzK BzK galaxies @ 1.4<z<2.5 galaxies @ 1.4<z<2.5

Daddi et al. (2004)

E(B-V)

Bruzual Bruzual & & Charlot Charlot (2003) (2003)

Passive BzKs Star-forming BzKs

B B z z’ ’ K K B B z z’ ’ K K

slide-4
SLIDE 4

Optical and NIR data in the Optical and NIR data in the SDF SDF

  • B, z

B, z’ ’, K , K

  • ptical : Subaru/
  • ptical : Subaru/Suprime

Suprime-

  • Cam

Cam NIR : UKIRT/WFCAM NIR : UKIRT/WFCAM

  • limiting

limiting mag.(AB mag.(AB, 2 , 2” ” aperture) aperture)

  • B : 28.8 (

B : 28.8 (２ ２σ σ) )

  • z

z’ ’ : 27.0 ( : 27.0 (２ ２σ σ) )

  • K : 23.5 (5

K : 23.5 (5σ σ) )

  • seeing : 1.14

seeing : 1.14” ”

  • areas used for clustering

areas used for clustering analysis analysis

  • NW area : ~100 arcmin

NW area : ~100 arcmin2

2

  • SW area : ~80 arcmin

SW area : ~80 arcmin2

2 WFCAM WFCAM Suprime Suprime-

  • Cam

Cam

NW NW SW SW

These areas are used for These areas are used for clustering analysis clustering analysis

slide-5
SLIDE 5

BzK BzK galaxies in the SDF galaxies in the SDF

star star-

  • forming

forming passive passive

B-z’ z’-K

KAB<23.5

K KAB

AB≦

≦23.2 23.2 BzK BzK’ ’s s samples samples

SW SW NW NW total total Star Star-

  • forming

forming 419 419 673 673 1092 1092 Passive Passive 20 20 36 36 56 56 (The limiting (The limiting magitude magitude of the

  • f the

samples is total magnitude.) samples is total magnitude.)

slide-6
SLIDE 6

Celestial distribution of Celestial distribution of BzKs BzKs

K KAB

AB≦

≦23.2 samples 23.2 samples

SW SW NW NW total total Star Star-

  • forming

forming 419 419 673 673 1092 1092 Passive Passive 20 20 36 36 56 56

Star-forming BzKs passive BzKs

NW SW

Star-forming BzKs passive BzKs

slide-7
SLIDE 7

Angular correlation function of Angular correlation function of star star-

  • forming

forming BzKs BzKs

KAB≦23.2

A=0.58 A=0.58± ±0.13 0.13 star-forming BzK

Measurements from the two Measurements from the two subregions subregions are averaged. are averaged.

  • ACF is assumed to be power law,

ACF is assumed to be power law, W( W(θ θ)=A )=Aθ θ-

  • 0.8

0.8

  • Errors are estimated using bootstrap resample method

Errors are estimated using bootstrap resample method (Error bars are 1 (Error bars are 1σ σ) )

  • The sample of passive

The sample of passive BzKs BzKs is too small to obtain a reliable result is too small to obtain a reliable result

slide-8
SLIDE 8

Translation of ACF into SCF Translation of ACF into SCF

  • ACF

ACF ⇒ ⇒ Spatial Correlation Function (SCF) Spatial Correlation Function (SCF)

  • ξ

ξ(r (r)=(r/r )=(r/r0

0)

) -

  • 1.8

1.8

r r0

0: correlation length

: correlation length

  • If

If redshift redshift distribution is known, distribution is known, r r0

0 is

is culculated culculated from amplitude of the ACF from amplitude of the ACF using Limber using Limber’ ’s equation. s equation.

correlation length (r correlation length (r0

0)

) ⇒ ⇒ DH DH mass mass

KAB≦23.2

A=0.58±0.13 ACF N(z)

  • N(z

N(z) of star ) of star-

  • forming

forming BzKs BzKs is assumed to is assumed to be a Gaussian with be a Gaussian with z zc

c=

=1.9 1.9、 、σ σ=0.35 =0.35± ±0.1. 0.1.

  • Histogram of

Histogram of N(z N(z) shows that of ) shows that of star star-

  • forming

forming BzKs BzKs with K<22. with K<22. （ （spectroscopic spectroscopic redshifts redshifts are contained. are contained.） ） ( (Daddi Daddi et al. 2004) et al. 2004)

slide-9
SLIDE 9

correlation length correlation length （ （r r0

0）

） and DH mass of and DH mass of star star-

  • forming

forming BzKs BzKs

The r The r0

0 of bright

  • f bright BzKs

BzKs is calculated from the ACF given in Kong et al. (2006) (K06). is calculated from the ACF given in Kong et al. (2006) (K06).

Brighter star Brighter star-

  • forming

forming BzKs BzKs are hosted by more massive dark haloes. are hosted by more massive dark haloes.

slide-10
SLIDE 10

The stellar mass and DH mass The stellar mass and DH mass

  • f star
  • f star-
  • forming

forming BzKs BzKs

DH mass DH mass 1010 1011 1012 1013 1014 1010 1011 1012 Stellar mass Stellar mass

S t e l l a r m a s s ＝ D H m a s s

The mass of dark The mass of dark-

  • haloes largely increases with the stellar mass.

haloes largely increases with the stellar mass.

slide-11
SLIDE 11

Comparison of correlation length Comparison of correlation length with other galaxy populations with other galaxy populations

  • faint (K

faint (KAB

AB<23.2) star

<23.2) star-

  • forming

forming BzK BzK

  • BX/BM @ z~2

BX/BM @ z~2

  • LBG @ z~3

LBG @ z~3 ⇒ ⇒ M MDH

DH~10

~1011

11Msun

Msun

  • bright (K

bright (KAB

AB<21.9) star

<21.9) star-

  • forming

forming BzK BzK

  • ERO @ z~1

ERO @ z~1-

  • 2

2

  • DRG @ z~2

DRG @ z~2-

  • 3

3

  • cluster @ z~0

cluster @ z~0 ⇒ ⇒ M MDH

DH~10

~1013

13-

  • 14

14Msun

Msun

Faint star Faint star-

  • forming

forming BzKs BzKs and optically selected star and optically selected star-

  • forming

forming galaxies at z~2 are similar populations. galaxies at z~2 are similar populations.

slide-12
SLIDE 12

Present Present-

  • day descendants

day descendants

  • f star
  • f star-
  • forming

forming BzKs BzKs

  • extended Press

extended Press-

  • Schechter

Schechter formalism formalism This formalism predicts the mass This formalism predicts the mass growth of dark growth of dark-

  • haloes.

haloes.

  • K

KAB

AB<20.4

<20.4 M MDH

DH(z

(z=2) = 1.6 =2) = 1.6× ×10 1014

14 Msun

Msun ⇒ ⇒ M MDH

DH(z~0) = 4.3

(z~0) = 4.3-

  • 9.3

9.3× ×10 1014

14 Msun

Msun

  • K

KAB

AB<23.2

<23.2 M MDH

DH(z

(z=2) = 2.8 =2) = 2.8× ×10 1011

11 Msun

Msun ⇒ ⇒ M MDH

DH(z~0) = 3.7

(z~0) = 3.7-

  • 10.0

10.0× ×10 1011

11 Msun

Msun

Star Star-

  • forming

forming BzKs BzKs evolve into galaxies over a wide range of mass, evolve into galaxies over a wide range of mass, depending on their apparent K brightness. depending on their apparent K brightness.

slide-13
SLIDE 13

summary summary

  • Faint star

Faint star-

  • forming

forming BzKs BzKs are hosted by less massive dark are hosted by less massive dark haloes with ~ 10 haloes with ~ 1011

11 Msun

Msun, while bright star , while bright star-

  • forming

forming BzKs BzKs are hosted by massive dark haloes with ~ 10 are hosted by massive dark haloes with ~ 1013

13-

  • 14

14 Msun

Msun. .

  • The mass of dark

The mass of dark-

  • haloes largely increases with the stellar

haloes largely increases with the stellar mass of star mass of star-

  • forming

forming BzK BzKs s. .

  • Faint star

Faint star-

  • forming

forming BzKs BzKs are similar populations to are similar populations to LBG LBGs s (BXs/BMs) at z~2, and then evolve to be less massive (BXs/BMs) at z~2, and then evolve to be less massive galaxies with 10 galaxies with 1011

11-

  • 12

12 Msun

Msun in the local universe. in the local universe.

  • Bright star

Bright star-

  • forming

forming BzKs BzKs evolve to be galaxies in massive evolve to be galaxies in massive clusters. clusters.

“ “Luminosity dependent clustering of star Luminosity dependent clustering of star-

  • forming

forming BzK BzK galaxies at galaxies at redshift redshift 2 2” ”, , Hayashi et al. 2007, astro Hayashi et al. 2007, astro-

  • ph/0701637 (accepted in

ph/0701637 (accepted in ApJ ApJ) )