Subaru Observations of Galaxy Clusters at z

Subaru Observations of Galaxy Clusters at z<1.3

Masayuki Tanaka (University of Tokyo)Tadayuki Kodama (NAOJ) + the PISCES team

Outline

1 – Observations

2 – Large-Scale Structures

3 – Color-Magnitude Diagrams

4 – Spectral Diagnostics

5 – Summary

1 – Observations

Mauna Kea Observatories

redshift

z=0

z=0.55(5.4Gyr)

z=0.83(7.0Gyr)

Object Photometry Spectroscopy

Sloan Digital Sky Survey u g r i z ~260,000 objects(DR2)

Suprime-Cam (Subaru) B V R i z FOCAS (Subaru) ~200 objects

Suprime-Cam (Subaru) V R i z FOCAS (Subaru) ~300 objects

CL0016

RXJ0152

CL0016 at z=0.55

ACS/HST

Color composition by Ichi Tanaka

Large-Scale Structures

CL0016 at z=0.55

Large-Scale Structures

CL0016 at z=0.55

spec. objects at0.54<z<0.56

spec. objects outside of 0.54<z<0.56

z=0.549

z=0.547

z=0.548

z=0.547

z=0.542

Someone et al in prep.

RXJ0152 at z=0.83Color composition by Ichi Tanaka

RXJ0152 at z=0.83

Large-Scale Structures

Tanaka et al. 2006 MNRAS 365, 1392

RXJ0152 at z=0.83

Large-Scale Structures

z=0.844

z=0.842

z=0.745

z=0.782

z=0.835

z=0.837

z=0.839

z=0.844

spec. objects at0.82<z<0.85

spec. objects outside of 0.82<z<0.85

Tanaka et al. 2006 MNRAS 365, 1392

RXJ1716 at z=0.81 MS1054 at z=0.83

RDCSJ0910 at z=1.1 RDCSJ1252 at z=1.24

Koyama et al. in prep.

Tanaka et al. MNRAS submitted

Structures around other high-z clusters

3 – Color-Magnitude Diagrams

Time

Color

Environment

luminosity

Cluster / Group / Field Environments

redshift

z=0 z=0.55 z=0.83

Tanaka et al. 2005 MNRAS 362, 268

Colour-Magnitude Diagrams

red

blue

z=0 z=0.55 z=0.83

redshift

massive less massive

Tanaka et al. 2005 MNRAS 362, 268

Giant-to-Dwarf ratio of red galaxies

z=0.8

z=0.5z=0

Tanaka et al. 2005 MNRAS 362, 268

Giant : 10.6<log (Msteller/Msolar)

Dwarf: 9.7 < log (Msteller/Msolar) < 10.6

Giant : 10.6<log (Msteller/Msolar)

Dwarf: 9.7 < log (Msteller/Msolar) < 10.6 Tanaka et al. 2005 MNRAS 362, 268

Giant-to-Dwarf ratio

z=0.8

z=0.5z=0

1) Galaxies follow the 'down-sizing' evolution.

2) The 'down-sizing' is delayed in low-density environments.

4 – Spectral Diagnostics

Composite Spectra of Red Galaxies at z~0.8

Tanaka et al. 2006 MNRAS 365, 1392

Model Star Formation Histories

time

star

form

atio

n ra

te

SSP modeltau model burst model

Bruzual & Charlot 2003 Model : Chabrier IMF between 0.1-100Msolar Solar Metallicity, No dust extinction

Spectral Diagnostics – SSP

model grids: Bruzual & Charlot 2003contours : galaxies at z=0

preliminary

Spectral Diagnostics – tau model

model grids: Bruzual & Charlot 2003contours : galaxies at z=0

preliminary

Spectral Diagnostics – burst model

model grids: Bruzual & Charlot 2003contours : galaxies at z=0

preliminary

5 – Summary

Schematic View of Galaxy Evolution

Env

iron

men

t

MassTime

Env

iron

men

t

MassTime

Schematic View of Galaxy Evolution

Env

iron

men

t

MassTime

Schematic View of Galaxy Evolution

Env

iron

men

t

MassTime

Schematic View of Galaxy Evolution

Env

iron

men

t

MassTime

Schematic View of Galaxy Evolution

Env

iron

men

t

MassTime

Schematic View of Galaxy Evolution