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Yuichi Matsuda (NAOJ)松田 有一(国立天文台)
Ly-alpha morphology-density
relation @ high-z
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1) Subaru / S-Cam survey shows a hint of Ly-alpha morphology-density relation at high-z.
2) Current observations are limited to extremely bright Ly-alpha blobs.
3) TMT will be able to study the morphology of the circum galactic medium of more normal galaxies at high-z.
Summary
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Ly-alpha imaging of the CGM• Lya imaging is a promising way to see the 2D
morphology of the gaseous structure around high-z galaxies (Chris Martin’s talk).
Dekel et al. (2009), van de Voort et al. (2011)
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Subaru Telescope + Suprime-Cam + Narrow-band filter 8.2 m 27’ x 34’ 21 x 17 cm R ~ 80
http://www.naoj.org/
Subaru / S-Cam Lya Survey at z=3 2.4 sq deg deep Lya imaging survey (Yamada+12) 12 pointings (SSA22 + 6 surrounding fields, Subaru Deep Field,
GOODS-N, Subaru-XMM Deep Survey Fields) 1-sigma Lya surface brightness~10-18 erg s-1 cm-2 arcsec-2 2200 Lya emitters (Yamada+12) 14 giant (>100kpc) Lya nebulae (Matsuda+11)
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2.4 sq deg deep Lya imaging survey (Yamada+12) 12 pointings (SSA22 + 6 surrounding fields, Subaru Deep Field,
GOODS-N, Subaru-XMM Deep Survey Fields) 1-sigma Lya surface brightness~10-18 erg s-1 cm-2 arcsec-2 2200 Lya emitters (Yamada+12) 14 giant (>100kpc) Lya blobs (Matsuda+11)
300kpc
Subaru / S-Cam Lya Survey at z=3
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The areas of blobs are measured above a threshold of 1.4x10-18
erg/s/cm2/arcsec2.
The circles have diameters of the major axis of the Lya blobs.
300kpc
Filamentary & Spherical Lya blobs
Covering Factor0
0.51
1.52
2.53
3.54
4.5
20-25%25-30%30-35%35-40%40-45%45-50%50-55%
Filamentary Spherical
20 25 30 35 40 45 50 55(%)
N
S S
S
S
S
F
FF F
F F
F
F
F
Subaru / S-Cam Lya Survey at z=3
Faucher-Giguere+11200 kpc 200 kpc
Matsuda+11
ObservationSimulation
Spherical?
Covering Factor ~60%
Subaru / S-Cam Lya Survey at z=3
Faucher-Giguere+11200 kpc 200 kpc
Matsuda+11
Filamentary?
ObservationSimulation
Covering Factor ~20%
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2.4 sq deg deep Lya imaging survey (Yamada+12) 12 pointings (SSA22 + 6 surrounding fields, Subaru Deep Field,
GOODS-N, Subaru-XMM Deep Survey Fields) 1-sigma Lya surface brightness~10-18 erg s-1 cm-2 arcsec-2 2200 Lyman-alpha emitters (Yamada+12) 14 giant (>100kpc) Lyman-alpha nebulae (Matsuda+11)
Subaru / S-Cam Lya Survey at z=3
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-0.5 1 30%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
SphericalFilamentary
Frac
tion
Surface Over Density of Lya Emitters(<5 Mpc)
Field Protocluster
Lya Morphology Density Relation?
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Local Morphology Density Relation
Dressler 80Fr
actio
n
Surface Density of galaxies
S + Irr
E + S0
Field Cluster
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• Filamentary Lya blobs may relate to disc galaxy formation via cold streams in the field.
• Spherical Lya blobs may relate elliptical galaxy formation in hot haloes in proto-cluster.
-0.5 1 30%
10%20%30%40%50%60%70%80%90%
100%SphericalFilamentary
Frac
tion
Over Density
Lya Morphology Density Relation?
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• Current observations are limited to extremely bright Lya blobs (only 14 sources!!).
• It is difficult to study the Lya morphologies of fainter normal galaxies individually.
-0.5 1 30%
10%20%30%40%50%60%70%80%90%
100%SphericalFilamentary
Frac
tion
Over Density
Lya Morphology Density Relation?
14
20”150kpc
High LowLAE surface density (5 Mpc/h smoothing)
Stacking analysis of 2200 LAEs
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The Lya radial profile of the field LAEs has a steeper slope.
Do the field LAEs (and LBGs) also have filamentary CGM structure?
If so, TMT will be able to detect the Lya emitting filaments around LAEs and LBGs.
8m 10hrs
30m 10hrs
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1) Subaru / S-Cam survey shows a hint of Ly-alpha morphology-density relation at high-z.
2) Current observations are limited to extremely bright Lya sources.
3) TMT will be able to study the morphology of the circum galactic medium of more normal galaxies at high-z.
Summary
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Conclusion
• Ly-alpha imaging is a promising way to study gaseous structure around high-z galaxies.
• Subaru / S-Cam survey shows a hint of Ly-
alpha morphology-density relation at high-z but the survey is limited to extreme cases.
• TMT will be able to observe the gaseous structure around more normal galaxies.
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1) Subaru / Suprime-Cam survey at z=3 shows a hint of Lyman-alpha morphology density relation.
2) Filamentary Lya nebulae are found in the field, while spherical nebulae are dominant in overdense regions.
3) Filamentary nebulae may relate to disc formation via cold streams in the field while the spherical nebulae may relate to spheroid formation in hot haloes in the proto-cluster.
Summary
Radial profile of stacked Lya image of 92 LBGs at z=2-3
Surface brightness threshold ~10-19 erg s-1 cm-2 arcsec-2
Lya
All UV-continuum selected galaxies at z=2-3 have diffuse extended Lya halos
Current survey threshold
Steidel+1120”
150kpc
But the data are from galaxy over-densities
What determines Lya spatial extent?
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Study Lya halos using 2128 LAEs at z=3.1 as a function of environment and UV luminosity (Matsuda+12)
LAE
surfa
ce d
ensit
y (5
Mpc
/h sm
ooth
ing)
Low
H
igh
Bright FaintCentral UV Luminosity
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Future Subaru HSC Survey• Hyper Suprime-Cam (1.5 deg diameter)• Subaru Strategic Program (300 nts in 5yrs)• Survey starts from Spring 2014• Including Deep z=2-7 Lya imaging in ~30 sq deg• http://www.naoj.org/Projects/HSC/surveyplan.html
Subaru Telescope + Hyper Suprime-Cam + Narrow-band filter 8.2 m 90 arcmin diameter 60 cm diameter
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Exponential fitting
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Bright FaintCentral UV luminosity
20”150kpc
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25
Expo
nenti
al sc
ale
leng
th
Low HighLAE surface density
(5 Mpc/h smoothing)
Faint BrightCentral UV luminosity
Exponential fitting