1. Molecular Gas (Excitation) at High Redshift Fabian Walter Max Planck Institute for Astronomy Heidelberg Fabian Walter Max Planck Institute for Astronomy Heidelberg A. Weiss (MPIfR) D. Downes (IRAM), D. Riechers (Caltech), C. Carilli (NRAO), F. Bertoldi (AIfA), P. Cox (IRAM), R. Wang (U Peking), E. Daddi (CES), Ran Wang (UA)

2. Molecular Gas with ALMA and EVLA

3. CO line SEDs: excitation and structure analysis multiple components LVG: n(H 2 ), T kin –>T b S ~ m Ω s b ff T b, m = magnification Ω s b ff =  r 0 2 b ff = source filling CO excitation free parameters n(H 2 ) T kin r 0 [CO]/[H 2 ]/dv/dr fixed to 10 -5 pc (km/s) -1

4. LVG model degeneracy well determined: Gas pressure (n T) equivalent radius L’ CO(1-0) T kin, n(H 2 ) ambiguity But: shape of the CO SED is temperature dependent! Solve ambiguity via: Dust (dust temperature, dust to gas mass ratio) Atomic Carbon (T ex ) APM08279 : log(nH 2 )=4.2 T kin =220K r=790pc log(nH 2 )=4.0 T kin =350K r= 700pc log(nH 2 )=5.4 T kin =40K r=1800pc T dust, T ex CI Dust to gas mass ratio

5. CO line SED of the MW COBE (Fixen etal 1999) CO(1-0) Dame, Hartmann & Thadeus 2001 inner disk diffuse dense outer disk GC

6. diffuse dense center Integrated CO SED M82 diffuse total M82 CO(1-0) M82 Walter et al. 2003 Weiss et al. 2005 molecular gas outflow. 2005

7. CO SEDs of local (U)LIRGs: Two components for all sources; SED peak ~ CO(4-3) Consistent with: LE: T kin ~ 30 K; n(H 2 ) ~ 10 3.2 cm -3 HE: T kin ~ 50 K; n(H 2 ) ~ 10 4.0 cm -3 CO(3-2) APEX2, CO(4-3) FLASH, CO(6-5) CHAMP+, CO(7-6) CHAMP CO(1-0) & CO(2-1) from SEST (Elfhag etal 1996, Aalto etal 1999) N986; log IR 10.8 N7130 log IR 11.4Arp186 log IR 11.6 N3256 log IR 11.6VV114 log IR 11.7F18293 log IR 11.8 I13120 log IR 12.3

9. CO line SEDs / Ladders IRAM 30m CO SED survey (1, 2, 3mm bands)

10. CO(1-0) Transition: ‘cm’ Telescopes Riechers, Walter, Carilli et al. 2006 GBT Effelsberg PSS J2322 (z=4.1) APM08279 (z=3.9) +

11. CO line SEDs at high-z CloverleafF10214 BR1202 APM0827 PSS1409MG0751RXJ0911 SMM04431HR10 SMM16359BSMM14011 J11148 SMM123549SMM163650SMM163658

12. T kin ~40 – 60 K (T dust ~ 50 K) n(H 2 ) ~ 10 3.6-4.3 cm -3 T kin ~ 200 K (T dust ~ 200 K) n(H 2 ) ~ 10 4.2 cm -3 Strongly lensed (m=80-100) central ~200pc surrounding the QSO. AGN heating! Normalized high-z CO SEDs T kin ~ 30-50 K (T dust ~ 30-50 K) n(H 2 ) ~ 10 2.7-3.5 cm -3 All sources ( 8 QSOs & SMGs, 7) are described by a single gas component CO excitation (peak of the CO SED) in SMGs is lower than in QSO hosts Molecular gas distributions are compact (r 0 = 0.3-1.2 kpc) Molecualr gas surface densities are high (    Msol pc -2  

13. T kin ~40 – 60 K (T dust ~ 50 K) n(H 2 ) ~ 10 3.6-4.3 cm -3 T kin ~ 200 K (T dust ~ 200 K) n(H 2 ) ~ 10 4.2 cm -3 Strongly lensed (m=80-100) central ~200pc surrounding the QSO. AGN heating! Normalized high-z CO SEDs T kin ~ 30-50 K (T dust ~ 30-50 K) n(H 2 ) ~ 10 2.7-3.5 cm -3 All sources ( 8 QSOs & SMGs, 7) are described by a single gas component CO excitation (peak of the CO SED) in SMGs is lower than in QSO hosts Molecular gas distributions are compact (r 0 = 0.3-1.2 kpc) Molecualr gas surface densities are high (    Msol pc -2  

14. Potential effect of galaxy merging on the CO SEDs L FIR, SFR, n(H 2 ) M51 Antennae Arp220Mrk 231 r CO ~ 4kpc r CO ~ 1.5kpc r CO ~ 500 pc r CO ~200 pc quiet disk galaxies Early mergers Advanced mergers & starbursts AGN heating

15. z~2 SF gal’s: not extreme starbursts, but massive gas reservoirs  6 of 6 detected in CO, ~10 kpc size  M gas > 10 10 M o ~ high-z HyLIRG (SMG, QSO host) But:  SFR < 10% HyLIRG  5 arcmin -2 (vs 0.05 for SMGs) => common, ‘normal’ high-z galaxies => common, ‘normal’ high-z galaxies Daddi ea. 2007, 2008, 2009 Linda’s talk 3.2” HST PdBI CO(2-1)

16.  CO excitation = Milky Way (but M gas > 10x MW)  L FIR /L’ CO = MW << ULIRGs/SMGs  Gas depletion timescales > few x10 8 yrs L FIR /L’ CO MW z~2 SF gal’s: Milky-Way like conditions for SF, not ULIRG-like BzK-21000 Milky Way low z high z Milky Way

17. ALMA/EVLA CO discovery space

18. QSO

19. SMG QSO

20. CO NOT EXCITED BzK SMG QSO …bad news for ISM studies in EoR! ALMA/EVLA CO discovery space

21. CO NOT EXCITED BzK SMG QSO …bad news for ISM studies in EoR! T CMB ! ALMA/EVLA CO discovery space

22. CO NOT EXCITED BzK SMG QSO …bad news for ISM studies in EoR! ALMA/EVLA CO discovery space

23. [CII] resolved at z=6.4 1.9THz line observed at 258 GHz beamsize: 0.35”, spatially resolved on 2kpc scales Direct evidence for formation of stellar disk/bulge in host galaxy < 1Gyr after big bang Bure rocks! Walter et al. 09 SFRSD=1000 M sun yr -1 kpc -2

24. C + at high z (Walter et al 2009; Maiolino et al 2005, 2009; Iono et al 2006; Bertoldi et al in prep)

25. Summary CO observations still workhorse for high-z studies CO observations still workhorse for high-z studies imaging and high density tracers great.... imaging and high density tracers great.........but excitation also provide key information......but excitation also provide key information. distinct differences in high-z galaxy populations distinct differences in high-z galaxy populations local universe: extremely bright future with Herschel local universe: extremely bright future with Herschel high-z: ALMA, but still needs quite some observing time. high-z: ALMA, but still needs quite some observing time. [CII] will be key diagnostic line for z>7 Universe for ALMA [CII] will be key diagnostic line for z>7 Universe for ALMA