初期宇宙における大質量星形成領域のプローブとしての遠赤外電離酸素

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初期宇宙における
大質量星形成領域のプローブとしての
遠赤外線電離酸素輝線
Hiroshi Matsuo (NAOJ)
Akio Inoue (Osaka Sangyo Univ.)
Atmospheric Windows from Atacama(alt. 4800m)
1mm
500um
300um
200um
2
Matsushita, Matsuo et al. PASJ (1999)
THz Cosmic Window
3
High-z universe beyond
redshift 8

To probe the period of Re-Ionization.
 Interstellar space should be already
contaminated by heavy elements from Pop III.
 High UV field prevent formation of dust,
hence low extinction.
 Massive stars are formed in clusters, nearby
counter parts are R136 in 30Dor, LMC.
 SFG and GRB can trace massive star clusters.
FIR SED of
Starburst galaxies

OI, OIII
 NII, NIII
 CII
Fischer et al. (1999)
FIR atomic fine structure lines

OI
– 63.185mm
– 145.54mm
4.745THz
2.060THz
5.0×105 cm-3
1.5×105 cm-3
5.786THz
3.393THz
3.4×103 cm-3
5.0×102 cm-3
2.461THz
1.460THz
2.8×102 cm-3
4.5×101 cm-3
5.229THz
3×103 cm-3
1.901THz
2.7×103 cm-3

OIII 35.1eV
– 51.815mm
– 88.356mm
 NII 14.5eV
– 121.80mm
– 205.30mm
 NIII 29.6eV
– 57.330mm
 CII 11.3eV
– 157.68mm
Carina Nebula by ISO LWS
[CII]
Mizutani, Onaka, Shibai. (2002)
The Carina Nebula
[CII] 158 mm
A very massive star-forming
region at 2.3 kpc
[NII] 122 mm
[OIII] 88 mm
from N. Smith
24’x12’ Hubble Image
Matsuo et al. (2009)
30Dor region and
R136
300 Mo stars
[OIII] 88mm is
observed widely
distributed around
R136
Contour: MIPS 24mm
Kawada et al. (2011)
Observation with ALMA

Primordial Massive Star-Forming Region
 [OIII] 52um, 88um (ion potential 35 eV)
– Probe of electron density and UV radiation

Z > 8 observation of SFGs and GRBs
 Site of Cosmic Re-ionization
Example of [OIII] observations
in submillimeter-wave
~ 10 -18 W/m2
Ferkinhoff (2010)
High-z Star-Forming Galaxies
M82
Line Intensity W/m2
10-17
[NeII]
[SiIII]
z=0.1
[OI] [OIII] [CII]
[OIII]
ALMA Bands
10 9
8
7
6
Herschel
z=0.2
10-18
z=0.5
10-19
SPICA
z=1
10-20
z=2
z=3
10-21
z=5
z=8
z=10
10 um
100 um
Wavelength
1 mm
[OIII] 88 mm line intensities

Single massive cluster
– 1 ×10-5 W/m2/sr
from Carina
– 10 arcmin in diameter @ 50 kpc from 30 Dor
7 × 10-11 W/m2 at z=10-5
2 × 10-22 W/m2 at z=8
1.7 mJy for 10 km/s @ 350 GHz
angular diameter 10 milli-arcsec
» Band 7: 339-364 GHz → [OIII]88 @ z=8.3—9.0!
» 感度は十分か?
˃ [OIII]88/Hα相関
(Kawada+11)
˃ Cloudy計算
で予想フラックスを推定
linear
2013/1/26
Kawada et al. 2011
14
ALMA時代の宇宙の構造形成理論研究会
» Kawada et al. 2011
˃ I_[OIII]88 / I_Hα ~ 2/3
˃ Hα / Hβ ~ 3 (Case B近似)
» Cloudy (Ferland et al. 1998)
˃ Z = 0.2 Zsun, log10(U) = -1.0, log10(n_H) = 0.0
𝐿[OIII]88
≈2
𝐿Hβ
» NOTE: nebula parameter dependence
2013/1/26
˃ Especially, metallicity
15
ALMA時代の宇宙の構造形成理論研究会
» z>8 candidates are detected only in rest-UV.
» [OIII] – UV relation is required.
» Let us relate Hβ with UV:
˃ SFR conversion laws (~100Myr constant SF):
𝐿Hβ = 1.6 × 1041 erg s−1
𝑆𝐹𝑅
𝑀sun yr −1
𝜈UV 𝐿𝜈
= 1.4 × 1043 erg s−1
UV
2013/1/26
𝐿Hβ
≈ 0.01
𝜈UV 𝐿ν UV
𝑆𝐹𝑅
𝑀sun
yr −1
For Z=1/5Zsun (Inoue 2011)
For Z=Zsun (Kennicutt 1998)
Lower Z: larger UV—SFR factor
Dust obscuration: smaller UV—SFR factor
16
ALMA時代の宇宙の構造形成理論研究会
» Kawada+11 obs.
» Cloudy calculations
» Hβ, UV – SFR relation
𝐿[OIII]88
𝐿Hβ
𝐿Hβ
𝜈UV 𝐿ν UV
≈2
≈ 0.01
» Finally, we obtain
2013/1/26
𝐹[OIII]88
≈ 0.02
𝜈obs 𝐹ν obs
𝜈obs = 𝜈UV /(1 + 𝑧)
17
ALMA時代の宇宙の構造形成理論研究会
2013/1/26
27.5—28.0 ABで
~1 mJy (100 km/s)
18
ALMA時代の宇宙の構造形成理論研究会
Expected Brightness

Gravitational lensed sources
– 25-26 mag at H160
– 10 mJy Dv=100km/s
– Limited redshift information

HUDF sources (Dec. -28deg)
– 27-28 mag at H160
– 2 mJy Dv=100km/s
– Many candidates at z~8
Redshift probability
distributions
Z=8.11 for [OIII] 88um
Z=8.74
» UDF12によりUV slopeの測定精度が向上
˃ β~-2
˃ Z~Zsun, no dust
OR
Z~0.1—0.2 Zsun with Av~1mag
(Dunlop et al. 2013)
Robertson et al. 2013
2013/1/26
» 十分に酸素はあるはず
23
ALMA時代の宇宙の構造形成理論研究会
» 赤方偏移z>8.3を狙うため、Y105-J125 > 1.6
を課し、Cycle1で観測条件の良い天体
» UDF092y-07580550 H160=27.1mag
˃ Y105-J125 > 2.4
» CANDY-2350049216 H160=27.0mag
˃ Y105-J125 > 2.3
» 残念ながら不採択
2013/1/26
˃ Too risky!
24
ALMA時代の宇宙の構造形成理論研究会
Schenker et al. 2013
2013/1/26
» BoRGやCANDELSにも<28AB天体が20個ほ
どある
25
ALMA時代の宇宙の構造形成理論研究会
2013/1/26
Ellis et al. 2013
26
ALMA時代の宇宙の構造形成理論研究会
High-z universe beyond
redshift 8

To probe the period of Re-Ionization.
 Interstellar space should be already
contaminated by heavy elements from Pop III.
 High UV field prevent formation of dust,
hence low extinction.
 Massive stars are formed in clusters, nearby
counter parts are R136 in 30Dor, LMC.
 SFG and GRB can trace massive star clusters.
宇宙背景放射観測の現状



宇宙赤外線背景放射(CIB) = 観測値 ー 前景放射
前景放射: 太陽系(黄道光)、銀河系(星、星間ダスト放射)
近赤外域には銀河の重ねあわせでは説明できない超過成分
黄道光(前景放射)
背景放射
CMB
系外銀河 第一世代の星
の重ねあわせ
Ly-?
From
S. Matsuura
(SUBARU, HST, Spitzer, BLAST)
28
Carinae Nebula at 2.3 kpc
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