Observing Molecules in the EoR

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Observing Molecules in the EoR
Pierre Cox IRAM Grenoble, France
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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/CC/H2
• Luminosities involved
• 3x1011 ltL/Lsunlt 1014

From Blain (2003)
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(No Transcript)
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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? LCO(1-0)
4.4 1010 K km/s pc2 Xco 1.8 M?/ K km/s pc2
Weiss et al. (2005)
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Subarcsecond Imaging Results

• lt 0.5 (4 kpc)
• ? 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

Tacconi, Neri, Chapmanm Genzel et al. (2006)
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J11485251 - The Most Distant QSO at
z6.42 Observing First Light at Radio Wavelengths
Fan et al. 2003 White et al. 2003
z-band (Keck Djorgovski et al.)

• z6.42 age870 Myr
• one of the first luminous sources
• MBH 1-5 x 109 Msun (Willot et al. 2003)
• Mdust 108 Msun (Bertoldi et al.
  2003)

Dust continuum at 1.2 mm
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CO(3-2) 46.6149 GHz
PdBI
continuum
VLA
Walter et al. 2003 Bertoldi et al. 2003
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• Mass
• MH2 2 x 1010 Msun
• Mdyn 3 x 109 sin-2(i) Msun
• Mass in C and O 3x107 Msun

• CO excitation in J11485251 (filled circles),
  compared to NGC 253 (dashed)
• LVG Model
• Tkin 100K, nH27x104 cm-3

Bertoldi et al. (2003)
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Resolving the CO emission in J11485251
VLA AB C array res. 0.15 (1 kpc)

• Two sources separated by 0.3
• (1.7 kpc at z6.4) containing each
• 5 x 109 Msun
• Not likely to be amplified
• If gravitationally bound,
• MDyn4.5x1010 Msun

CO 3-2 at 45GHz
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• Early enrichment of heavy elements (z_sf gt 8)
• Integration times hours to days on HLIRGs

Walter et al. 2004
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CII 158 microns and CI emission lines in
J11485251 at z6.42Probing the physics of a
PDR at the end of the re-ionisation epoch
CO(7-6)
CII
CI(1-0)
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Other High Density Tracer HCN, HNC and HCO
APM082795255 (z3.91)
HCO(5-4)
HNC(5-4)
HNC(5-4) CN(5-4)
L(HCO) 4 x 1010 K/(km/s pc2) HCO(5-4)/HCN(5-4
) 1 HNC(5-4)/HCN(5-4) 0.9
Wagg et al. 2005 Burillo et al. 2006 Guelin,
Salome et al. 2006
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ALMA/EVLA/GBT Redshift coverage for CO
Epoch of Reionization
VLA CO(3-2), PdBI CO 6-5, 7-6 in J11485251 _at_
z6.42
Other lines HCN, HCO, CI, CII, H2O
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SKA and CO
M 82
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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

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Complementarity Line sensitivity
z5 SFR10M_sun/yr
High order, C
Low order transitions
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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 zgt4 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)
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Complementarity continuum sensitivity
AGN, star formation
dust
Stars, ionized gas
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SKA into the EoR Low Order Molecular Lines, Star
Formation

• 11485651 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 gt 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 zgt6, in few hours
• Determine redshifts directly from molecular
  lines

z6.55
SFRgt10 M_sun/yr
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The Future (is now) Probing the EoR!

• Study physics of the first luminous sources
• This can only be done at near-IR to radio
  wavelengths
• Currently limited to pathological systems
  (HLIRGs)
• SKA and ALMA 10-100 more sensitive which is
  critical for the study of normal galaxies

z6.4