October 27, 2006 SKA Workshop, Paris

Observing Molecules in the EoRObserving Molecules in the EoR

Pierre CoxIRAM

Grenoble, France

October 27, 2006 SKA Workshop, Paris

• 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

Luminosities involved:

3x1011 <L/Lsun< 1014

The spectrum of a ULIRG: a `field guide’

From Blain (2003)

October 27, 2006 SKA Workshop, Paris

LVG solution Cloverleaf CO LVG solution:CO LVG solution:Disk radius: 1 kpc Disk radius: 1 kpc excellent agreement with lens models !excellent agreement with lens models !log(n(Hlog(n(H22)) = 4.2 cm)) = 4.2 cm-3-3

TTkinkin = 30 K = 30 K

M(HM(H22) = 8 10) = 8 101010 M M

L’L’CO(1-0)CO(1-0) = 4.4 10 = 4.4 101010 K km/s pc K km/s pc22

XXcoco = 1.8 M = 1.8 M/ K km/s pc/ K km/s pc2 2

Weiss et al. (2005)

October 27, 2006 SKA Workshop, Paris

< 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 bulgesFulfill 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

Subarcsecond Imaging Results

Tacconi, Neri, Chapmanm Genzel et al. (2006)

October 27, 2006 SKA Workshop, Paris

J1148+5251 - The Most Distant QSO at J1148+5251 - The Most Distant QSO at z=6.42z=6.42

Observing First Light at Radio Observing First Light at Radio WavelengthsWavelengths

Gunn Peterson trough

Fan et al. 2003; White et al. 2003

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)

z-band (Keck – Djorgovski et al.)

Dust continuum at 1.2 mm

October 27, 2006 SKA Workshop, Paris

Walter et al. 2003Bertoldi et al.

2003

CO(3-2)46.6149 GHz

continuum

PdBI

VLA

October 27, 2006 SKA Workshop, Paris

Mass: Mass: MMH2 H2 = 2 x 10= 2 x 101010 M Msunsun

MMdyn dyn = 3 x 10= 3 x 1099 sin sin-2-2(i) (i) MMsunsun

Mass in C Mass in C and O: ~3x10 O: ~3x1077 MMsunsun

CO excitation in J1148+5251 (filled CO excitation in J1148+5251 (filled

circles), compared to NGC 253 (dashed)circles), compared to NGC 253 (dashed)

LVG Model:LVG Model:

TTkinkin= 100K, n= 100K, nH2H2=7x10=7x104 4 cmcm-3-3

Bertoldi et al. (2003)

October 27, 2006 SKA Workshop, Paris

VLA A+B + C array; res.: 0.15” (~1 kpc)

Resolving the CO emission in J1148+5251

Two sources separated by 0.3” Two sources separated by 0.3” (1.7 kpc at z=6.4) containing (1.7 kpc at z=6.4) containing each each

5 x 105 x 1099 M Msunsun

Not likely to be amplifiedNot likely to be amplified

If gravitationally bound, If gravitationally bound, MDyn=4.5x1010 Msun

Walter et al. 2004

CO 3-2 at 45GHz

1” Early enrichment of heavy elements (z_sf > 8)

Integration times: hours to days on HLIRGs

October 27, 2006 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 re-

ionisation epoch

CO(7-6)

CI(1-0)

CII

October 27, 2006 SKA Workshop, Paris

Other High Density Tracer: HCN, HNC and HCO+

Wagg et al. 2005; Burillo et al. 2006; Guelin, Salome et al. 2006

APM08279+5255 (z=3.91)

L’(HCO+) = 4 x 1010 K/(km/s pc2)HCO+(5-4)/HCN(5-4) ~ 1HNC(5-4)/HCN(5-4) ~ 0.9

HCO+(5-4)

HNC(5-4) & CN(5-4)

HNC(5-4)

October 27, 2006 SKA Workshop, Paris

ALMA/EVLA/GBT Redshift coverage for CO

VLA CO(3-2), PdBI CO 6-5, 7-6 inJ1148+5251 @ z=6.42

Epoch of Reionization

Other lines: HCN, HCO+, CI, CII, H2O

October 27, 2006 SKA Workshop, Paris

SKA and CO

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

Low order transitions

High order, C+…

z=5

SFR=10M_sun/yr

October 27, 2006 SKA Workshop, Paris

Radio studies of the first luminous objects

CO (+other molecules) at z>4

VLA:inhrs for L_FIR = 1e13 M_sun (‘HLIRG’)

SKA (20 – 40 GHz): 3in 3hrs for L_FIR =1e11 M_sun (‘LIRG’)

RadioContinuum studies of star forming

galaxies

1e13 L_sun

1e12 L_sun

1e11 L_sun

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 ), star forming galaxies, like M51, at z>6, in few hours

Determine redshifts directly from molecular lines

z=6.55

SFR>10 M_sun/yr

October 27, 2006 SKA Workshop, Paris

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

z