1. MAHALO-Subaru collaboration
TMT science Asahi-seimei building, 16/10/2013
From MAHALO-Subaru to ALOHA-TMT: unveiling internal physics of distant galaxies across environment
Yusei Koyama (NAOJ)
T. Kodama (NAOJ), K.I. Tadaki (NAOJ), M. Hayashi (Tokyo), I. Tanaka (Subaru), R. Shimakawa (Sokendai), and
MAHALO-Subaru collaboration

2. Outline - MAHALO-Subaru quick overview
Thank you !
- MAHALO-Subaru quick overview
Hello !
- Prospects for TMT era (ALOHA-TMT)
- Summary & Conclusions

3. Galaxy properties vs. Environment
“ Morphology–Density Relation”
(Dressler 1980)
Spiral
red, old, low SF activity E S0
blue, young, high SF activity
Low-density
High-density

4. MAHALO-Subaru project
Collaborators: T.Kodama (PI), M.Hayashi, K.Tadaki, I.Tanaka, R.Shimakawa
MApping H-Alpha and Lines of Oxygen with Subaru
Narrow-band Ha/[OII] emission-line survey for 0.4<z<2.5
Tadaki+’12
Koyama+’13a
Hayashi+’12

5. Subaru: big advantage with wide FoV
z = 30
z = 5
z = 3
MOIRCS
z = 2
z = 1
z = 0
MOIRCS
(4’ x 7’)
Suprime-Cam (34’ x 27’)
M=6×10^14 Msun, 20Mpc×20Mpc (co-moving)
Yahagi et al. (2005)

6. High-z structures revealed by MAHALO
(Hayashi+10, 11)
z=2.2
z=0.4
z=1.5
Many strong emitters
in z>1.5 cluster cores
(Koyama+13)
(Koyama+11)
(Tadaki+12)
z=0.8
z=2.5
z=1.6
(Koyama+10)
(Hayashi+12)

7. From L(Ha) + M★-dependent dust correction
SF main sequence is independent of environment out to z~2 (as far as we rely on Ha-based SFR).
From L(Ha) + M★-dependent dust correction
From rest-frame
R-band photometry
+ M/L correction
(Koyama et al. 2013b, MNRAS, 434, 423)

8. Beyond the SF Main Sequence
(two important caveats)

9. Dust extinction depends on environment
Cluster SF galaxies tend to be dustier – different SF mode?
A(Ha) from
SFR(IR)/SFR(Ha)
z=0.4 HAE sample
A(Ha) from
A(Ha)-M* relation
(calibrated at z=0)
(Koyama et al. 2013b, MNRAS, 434, 423)

10. “Mass segregation” in z>2 proto-cluster
SF galaxies in z>2 proto-cluster show redder colours and higher M* (>1011M) compared to general field galaxies.
: 24um-source
■： red HAE (dusty SF)
　　(J-KAB>1.4, DRG)
■： green HAE
　 (0.8<J-KAB<1.4)
■： blue HAE
(J-KAB<0.8)
(Koyama et al. 2013a, MNRAS, 428, 1551) 10

11. ALOHA-TMT Towards the TMT era Anatomy with Lines of Oxygen
and Hydrogen with AO on TMT

12. HST morphologies of Ha emitters at z=2
z~2 proto-cluster galaxies (rest-UV)
cluster phenomena !
z=2.2 HAEs
in PKS1138
M: 24um source
X: X-ray source
HST/i-band snapshots
(4”x4”=30 kpc for each)
(Koyama et al. 2013a) 12

13. ALOHA [1]: (Dust-corrected) Ha mapping
rest-UV Ha
Ha-strong
(but UV-faint) dusty red clumps. Responsible for major SF activity in these galaxies?
(seeing)
red clump
HST image
(ACS+WFC3)
rest-UV
Deep TMT+IFU observation will allow us to map Ha/Hb ratio (i.e. extinction map) over the galaxies. Ha
HST image
(ACS+WFC3)
(seeing)
Ha emitters at z=2.5 in SXDF/CANDELS from Tadaki et al. (2013)

14. ALOHA [2]: Spatially-resolved line ratios
Mapping multiple emission-lines over the galaxies allow us to unveil central AGN, metallicity gradient, excitation state… etc.
AGN in the central region
Purely star-forming
Redder symbols show galaxy central pixels
Pixel-by-pixel BPT diagram from SINFONI+AO observation (Newman et al. 2013)

15. ALOHA [3] : Galaxy dynamics with IFU
Recent discovery: high-z clumpy (field) galaxies are disk-rotating.
Disk/merger classification with
“kinemetry”
merger
disk
Genzel et al. (2006)
Shapiro et al. (2008)
Forster-Schreiber et al. (2011)

16. ALOHA-TMT will give us a direct answer !!
ALOHA [3] : Galaxy dynamics with IFU
Is it really true for high-z “cluster” galaxies as well?
(and for more normal, low-mass galaxies?)
rest-UV (ACS)
rest-UV (ACS)
Proto-cluster (z=2)
General Field (z=2)
Koyama et al. (2013)
Tadaki et al. (2013)
ALOHA-TMT will give us a direct answer !!

17. Summary
(1) MAHALO-Subaru unveiled large-scale structures at z>>1 with wide-field emission-line galaxy survey with Subaru.
(2) Using MAHALO sample, we find that SF main sequence is independent of environment at any time in the history of the universe since z~2 (as far as we rely on the Ha-based SFRs).
(3) SF galaxies in cluster environments may be more highly obscured by dust – implying a different mode of SF activity from general field galaxies.
(4) SF galaxies in z~2 proto-cluster environments tend to be more massive (and have higher SFR) than the field counterparts.
(5) High-z galaxies are clumpy (both in clusters and fields). ALOHA-TMT will reveal the environmental impacts on the internal physics of high-z galaxies with deep IFU observation.