Transcript Bertoldi et al. 2003

Observing Molecules in the EoR
October 27, 2006
SKA Workshop, Paris
Pierre Cox
IRAM
Grenoble, France
The spectrum of a ULIRG: a `field guide’
• Non-thermal radio
• Thermal dust
- Dominated luminosity
- Hotter in AGN
- Mid-IR spectral features
(missing in AGN)
• Molecular and atomic lines
- mm CO/HCN
- far-IR: C/N/O
- mid-IR: C-C/C=C/H2
From Blain (2003)
October 27, 2006
Luminosities involved:
3x1011 <L/Lsun< 1014
SKA Workshop, Paris
October 27, 2006
SKA Workshop, Paris
LVG solution Cloverleaf
CO LVG solution:
Disk radius: 1 kpc
excellent agreement with lens models !
log(n(H2)) = 4.2 cm-3
Tkin = 30 K
M(H2) = 8 1010 M
L’CO(1-0) = 4.4 1010 K km/s pc2
Xco = 1.8 M/ K km/s pc2
Weiss et al. (2005)
Subarcsecond Imaging Results
 < 0.5” (4 kpc)
Tacconi, Neri, Chapmanm Genzel et al. (2006)
October 27, 2006
SKA Workshop, Paris
 Compact sources
 Scaled-up versions and
more gas-rich of the local
ULIRG population
 Central densities and
potential well depths
comparable to those of
elliptical galaxies or
massive bulges
Fulfill the criteria of
maximal starbursts: initial
gas reservoir 1010-11 Msun is
converted to stars on a
timescale ~3-10 tdyn or a few
108 yr
J1148+5251 - The Most Distant QSO at z=6.42
Observing First Light at Radio Wavelengths
Gunn Peterson trough
Fan et al. 2003; White et al. 2003
z-band (Keck – Djorgovski et al.)
 z=6.42; age~870 Myr
 one of the first luminous sources
 MBH ~ 1-5 x 109 Msun (Willot et al. 2003)
 Mdust ~ 108 Msun
(Bertoldi et al. 2003)
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SKA Workshop, Paris
Dust continuum at 1.2 mm
CO(3-2)
46.6149 GHz
PdBI
continuum
VLA
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SKA Workshop, Paris
CO excitation in J1148+5251 (filled
circles), compared to NGC 253 (dashed)
 Mass:
LVG Model:
MH2 = 2 x 1010 Msun
Tkin= 100K, nH2=7x104 cm-3
Mdyn = 3 x 109 sin-2(i) Msun
 Mass in C and O: ~3x107 Msun
Bertoldi et al. (2003)
October 27, 2006
SKA Workshop, Paris
Resolving the CO emission in J1148+5251
VLA A+B + C array; res.: 0.15” (~1 kpc)
CO 3-2 at 45GHz
 Two sources separated by 0.3”
(1.7 kpc at z=6.4) containing each
5 x 109 Msun

Not likely to be amplified

If gravitationally bound,
MDyn=4.5x1010 Msun
1”
 Integration times: hours to
days on HLIRGs
Walter et al. 2004
October 27, 2006
 Early enrichment of heavy
elements (z_sf > 8)
SKA Workshop, Paris
[[CII] 158 microns and [CI] emission lines
in J1148+5251 at z=6.42
Probing the physics of a PDR at the end of the reionisation epoch
CO(7-6)
CII
CI(1-0)
October 27, 2006
SKA Workshop, Paris
Other High Density Tracer: HCN, HNC and HCO+
APM08279+5255 (z=3.91)
HCO+(5-4)
HNC(5-4)
HNC(5-4) & CN(5-4)
Wagg et al. 2005; Burillo et al. 2006;
Guelin, Salome et al. 2006
October 27, 2006
L’(HCO+) = 4 x 1010 K/(km/s pc2)
HCO+(5-4)/HCN(5-4) ~ 1
HNC(5-4)/HCN(5-4) ~ 0.9
SKA Workshop, Paris
ALMA/EVLA/GBT Redshift coverage for CO
Epoch of Reionization
VLA CO(3-2), PdBI
CO 6-5, 7-6 in
J1148+5251 @ z=6.42
Other lines: HCN, HCO+,
CI, CII, H2O
October 27, 2006
SKA Workshop, Paris
SKA and CO
M 82
October 27, 2006
SKA Workshop, Paris
SKA and ALMA: Optimal CO searches
 SKA/ALMA – comparable speed at 22 GHz, SKA clearly faster at 43 GHz
(FoV, fractional bandwidth, sensitivity)
 SKA/ALMA – complementary: high vs. low order transitions
October 27, 2006
SKA Workshop, Paris
Complementarity: Line sensitivity
z=5
SFR=10M_sun/yr
High order,
C+…
Low order transitions
October 27, 2006
SKA Workshop, Paris
Radio studies of the first luminous objects
Radio Continuum
studies of star forming
galaxies
1e13 L_sun
1e12 L_sun
1e11 L_sun
CO (+other molecules) at z>4
VLA: 3s in 3 hrs for L_FIR = 1e13 M_sun (‘HLIRG’)
SKA (20 – 40 GHz): 3s in 3hrs for L_FIR =1e11 M_sun (‘LIRG’)
October 27, 2006
SKA Workshop, Paris
Complementarity: continuum sensitivity
AGN, star formation
dust
Stars, ionized gas
October 27, 2006
SKA Workshop, Paris
SKA into the EoR: Low Order Molecular Lines, Star Formation
1148+5651: Hyperluminous IR galaxies
 Detect low order CO emission in seconds, including
imaging on subkpc scales.
 Detect high dipole moment molecules (HCO+,
HCN…) in minutes (critical densities > 1e5 cm^-3).
 Image non-thermal emission associated with star
formation and/or AGN at mas resolution.
Studying 1st galaxies
 Detect ‘normal’ (eg. Ly a), star forming
galaxies, like M51, at z>6, in few hours
 Determine redshifts directly from molecular
lines
October 27, 2006
SKA Workshop, Paris
z=6.55
SFR>10 M_sun/yr
The Future (is now): Probing the EoR!
• Study physics of the
first luminous sources
z=6.4
• This can only be done
at near-IR to radio
wavelengths
• Currently limited to
‘pathological’ systems
(HLIRGs)
• SKA and ALMA 10100 more sensitive
which is critical for the
study of ‘normal’
galaxies
October 27, 2006
SKA Workshop, Paris