MOIRCS and FMOS MOIRCS and for cluster studies

MOIRCS and FMOS MOIRCS and for cluster studies Ichi Tanaka Astronomical Institute, Tohoku University

Contents: 1. Intruduction and the current status of MOIRCS 2. MOIRCS and FMOS 3. Distant cluster studies as a target of FMOS-MOIRCS joint project

1. Intruduction and Current Status of MOIRCS

MOIRCS: Multi-Object Infrared Camera and Spectrograph for Subaru T. Ichikawa T. Nishimura C. Tokoku R. Suzuki Y. Katsuno & K. Omata/ M. Konishi/ T. Yoshikawa et al.

Performance of MOIRCS F. O. V 4' × 7' Observing Mode Imaging / MOS (cooled slits / Grizm) Optimized wavelength 0. 8 - 2. 5 um Spectral Resolution 500 ～ 1300 (2000) @ 0. 5”slit Detector HAWAII-2 (Hg. Cd. Te) x 2 Pixel Size 18 um Image Scale 0. 117 arcsec/pixel Readout noise / Q. E. <10 e- (TBD) / ~60% Slits about 50 slits per mask Slit Capacity ~24 Expected effeciency Imaging: 0. 34 Spectroscopy: 0. 20 Limiting Magnitude Imaging（1 hr、S/N=10） J=23. 8, H=23. 1, K=22. 3 Spectroscopy（R=500, 4 hr, S/N=5) J=21. 3, H=20. 8, K=20. 0

Large FOV: CISCO versus MOIRCS (From GOODS 6 hr Ks data)

This is the MOIRCS view! 4' x 7'

Components of MOIRCS Slit mask exchange unit Main dewar optics detector Support structure Peripherals Suzuki et al. Subaru UM 2002

Optical Unit/ Bench/ Filter/ Grism Slit Exchanging Unit Peripherals Support Structure/ Connector Main Dewer Detector

The Design of MOIRCS --- dual camera & spectrograph system Light MOS plate exchanging unit Focal Plane Cooler Filters/ Grism Cooler detector Front View Inside is Cooled to 77 K Side View

OPTICAL Rayout of MOIRCS

Imaging mode Object on the center is devided Spectrograph mode 4 arcmin. Usable for Spectroscopy! Unusable detector area (imaging) ~30 arcsec

MOIRCS is the MOS in z. JHK! Cooled mask slot / robotic mask in-out mechanism Max 50 slitlets / 24 masks available for a night

Grisms: R=500 gratings for z. J / HK wavebands R=1300 for J, H, K bands z. J R 500 HK R 500

Slit Mask Exchanging Unit Linear Actuator （can handle 0. 01 mm accuracy） Gate Valve Mask Dewar is detachable. with the exclusive cooler (cooled to 150 K) can hold 24 slit masks Useful for efficient mask exchange!

Slit mask exchanging mechanism ◎Procedure 1．Setting mask, vacuuming, cool down 2．Rotate corrousel for selecting mask 3. Gate valve opens, grab a mask by robot arm 4. pick up a mask, rotate, set to the focal plane 5. Close Gate valve, start obs. (~15 minutes. ) Room temperature test is successful

First Light is soon. Current plan: early March, 2004 !!! MOIRCS Science Workshop: Feb. 27/28 in Sendai !!! Registeration deadline … Jan. 31, 2004 A planned GT science will be intensively introduced and discussed on WS. Contributions are greatly welcomed!

2. MOIRCS and FMOS Comparison for scientific purpose

MOIRCS and FMOS: R=700 - 2400 z. JH with OHS 400 in 30' FOV. MOIRCS: R=500 - 1300 z. JHK <50 in 4'x 7' FOV. ECHIDNA Rayout FMOS … sparsely distributed targets => e. g. Field Objects MOIRCS … high density region => e. g. Clusters

MOIRCS and FMOS Suprime-Cam F. O. V. FOCAS F. O. V. MOIRCS FOV FMOS: MOIRCS: Good match to Suprime-Cam --- photo-z Good match to FOCAS --- optical spectroscopy

For General Field Survey • MOIRCS & FOCAS … pensil beam survey for whole galaxies [rest optical spectra for all galaxies, but still large cosmic variance] • FMOS & Sp. Cam-WFCAM … much less cosmic variance [good for large-scale clustering, global cosmic SFR history, & follow -up of the rare objects (sub-mm sources/ EROs/ AGNs) but needs a careful target selection by photo-z] *** Only FMOS can do an efficient follow-up of Sup. Cam 30'x 30'data *** For Studies of Cluster environment … FMOS-MOIRCS joint observation is most efficient!

3. Distant Cluster Sudies as a Target of FMOS-MOIRCS Joint Project

Distant Clusters of Galaxies Topic: • Star-formation activities in cluster environment • Large-scale clustering and star-formation • Early-epoch of clusters How the star-formation activities has ceased in clusters? What is the relationship between the dynamical evolution of clusters and the galaxy evolution in clusters? What properties do massive cluster galaxies have in their very young epoch?

For understanding galaxy evolution in cluster environment … • SFR measurement: Ha, Hb, [OII] (lines) …MOIRCS/FMOS Hd absorption (continuum for z>1 FMOS OHS!) üHigh density regions … MOIRCS (z>1); FOCAS(z<1) üGalaxies in the outskirts of clusters … FMOS • Structure, cluster dynamics: often >10 Mpc … FMOS! … no efficient way to do optical spectroscopy for faint galaxies! üComplex cluster merger ・・・ < a few Mpc …MOIRCS

A supercluster at z=0. 54 Connolly et al. (1996) known clusters at z=0. 54 Galaxies with pectroscopic redshift~0. 54 Galaxies with photometric redshift~0. 54 Suprime-Cam data by the PISCES project (Kodama et al. )

CL 0016

A supercluster search for a large QSO group at z=1. 1 LQG 10 … group of 23 QSOs at z~1. 1 (Crampton et al. 1989) : LSS at z~1. 1? Pilot works by Tanaka et al. (2000, 2001), Yamada et al. (1997) Area A. Area C. Our observed area by Suprime-Cam (i', z') Area B. 2 degrees

Results i’-z’ color selection for old red glalaxies at z=1. 1 … some hint for superstructure associated with LQG 10 Area A Area B Density enhancement mildly traces QSO distribution

Area A. ? Area C. highest density peaks. Area ・・・ MOIRCS/FOCAS is good B. Others … only sparsely distributed The whole structure / galaxy properies at the outskirts of clusters ==> ONLY FMOS can access!

Example of the hottest X-ray cluster RXJ 1347. 5 -1145 Sup. Cam data by Miyazaki (private) Redshift by Cohen &Kneib (2002) Substructure? 47 spectra … still not enough S-Z by Komatsu et al. (2001)

PISCES project (Subaru press relase 2003) Distant clusters …. More complex! Examples of two clusters at z=0. 8 Gioia et al. (1999)

Summary • MOIRCS will soon achieve First Light (Workshop on 27 -28 Feb. ) • FMOS, MOIRCS & Suprime-Cam can make up a good inter-collaborative project for intensive studies of cluster environments at z>1.