HerCULES. Paul van der Werf. Leiden Observatory. Lorentz Centre February 28, 2012

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1 Paul van der Werf Leiden Observatory Lorentz Centre February 28, 2012

2 Introducing Herschel Comprehensive (U)LIRG Emission Survey Open Time Key Program on the Herschel satellite 2

3 Who is? Paul van der Werf (Leiden; PI) Susanne Aalto (Onsala) Lee Armus (Spitzer SC) Vassilis Charmandaris (Crete) Kalliopi Dasyra (CEA) Aaron Evans (Charlottesville) Jackie Fischer (NRL) Yu Gao (Purple Mountain) Eduardo González-Alfonso (Henares) Thomas Greve (Copenhagen) Rolf Güsten (MPIfR) Andy Harris (U Maryland) Chris Henkel (MPIfR) Kate Isaak (ESA) Frank Israel (Leiden) Carsten Kramer (IRAM) Edo Loenen (Leiden) Steve Lord (NASA Herschel SC) Jesus Martín-Pintado (Madrid) Joe Mazzarella (IPAC) Rowin Meijerink (Leiden) David Naylor (Lethbridge) Padelis Papadopoulos (Bonn) Dave Sanders (U Hawaii) Giorgio Savini (Cardiff/UCL) Howard Smith (CfA) Marco Spaans (Groningen) Luigi Spinoglio (Rome) Gordon Stacey (Cornell) Sylvain Veilleux (U Maryland) Cat Vlahakis (Leiden/Santiago) Fabian Walter (MPIA) Axel Weiß (MPIfR) Martina Wiedner (Paris) Manolis Xilouris (Athens) 3

4 Conditions in ULIRGs Starbursts cannot be simply scaled up. More intense starbursts are also more efficient with their fuel. ULIRGs: Milky Way : Galactic GMCs: OM C-1: Orion BN - KL: L M FIR H L 1.5 L 1.8 L 54 L 400 L M M M M M L IR /L CO SFR/M H 2 1 SFE 1 L IR SFR (Gao & Solomon 2001) 4

5 (U)LIRGs (L IR >10 (11)12 L ) (Evans et al.) 5

6 (U)LIRGs from low to high z (Magnelli et al. 2011) LIRGs dominate cosmic star formation at high redshift 6

7 ISM in luminous high-z galaxies (Danielson et al. 2010) (Weiß et al. 2007) Even in ALMA era, limited spatial resolution on high-z galaxies. For unresolved galaxies, multi-line spectroscopy will be a key diagnostic 7

8 in a nutshell will uniformly and statistically measure the neutral gas cooling lines in a flux-limited sample of 29 (U)LIRGs. Sample: all IRAS RBGS ULIRGs with S 60 > Jy (6 sources) all IRAS RBGS LIRGs with S 60 > 16.8 Jy (23 sources) Observations: SPIRE/FTS full high-resolution scans: 200 to 670 m at R 600, covering CO 4 3 to and [CI] + any other bright lines PACS line scans of [CII] and both [OI] lines All targets observed to same (expected) S/N Extended sources observed at several positions 8

9 sample Target log(l IR /L ) Mrk IRAS F IRAS Arp Mrk IRAS F Arp NGC IRAS F Arp IC NGC NGC NGC Target log(l IR /L ) IC 4687/ NGC NGC MCG Mrk IRAS NGC Zw NGC NGC IRAS F NGC NGC NGC NGC

10 Mrk231 At z=0.042, one of the closest QSOs (D L =192 Mpc) With L IR = L, the most luminous ULIRG in the IRAS Revised bright Galaxy Sample Warm infrared colours Star-forming disk (~500 pc radius) + absorbed X-ray nucleus Face-on molecular disk, M H 2 ~ M HST/ACS (Evans et al., 2008) 10

11 Warning: may contain... quiescent molecular (and atomic) gas star-forming molecular gas (PDRs) AGN (X-ray) excited gas (XDRs) cosmic ray heated gas shocks mechanically (dissipation of turbulence) heated gas warm very obcured gas (hot cores) 11

12 Mrk231 SPIRE FTS (Van der Werf et al., 2010) 12

13 Mrk231 SPIRE FTS 13

14 Mrk231 SPIRE FTS 14

15 Mrk231 SPIRE FTS 15

16 Mrk231 SPIRE FTS 16

17 Mrk231 SPIRE FTS 17

18 Mrk231 SPIRE FTS 18

19 CO excitation 2 PDRs + XDR 6.4:1:4.0 n=10 4.2, F X =28 * n=10 3.5, G 0 = n=10 5.0, G 0 = * 28 erg cm -2 s -1 G 0 =

20 CO excitation 3 PDRs 6.4:1:0.03 n=10 6.5, G 0 = n=10 3.5, G 0 = n=10 5.0, G 0 =

21 High-J lines: PDR or XDR? High-J CO lines can also be produced by PDR with n= cm 3 and G 0 =10 5, containing half the molecular gas mass. Does this work? G 0 =10 5 only out to 0.3 pc from O5 star; then we must have half of the molecular gas and dust in 0.7% of volume. With G 0 =10 5, 50% of the dust mass would be at 170K, which is ruled out by the Spectral Energy Distribution [OH + ] and [H 2 O + ] > 10 9 in dense gas requires efficient and penetrative source of ionization; PDR abundances factor lower Only XDR model works! 21

22 Analysis of analysis Model not unique At least 9 free parameters, not really a proper fit Reasonable, based on prior knowledge External constraints available for all 3 components... but what if we did not have this prior knowledge? role of H 2 O role of shocks role of OH + 22

23 Modeling-free result Highly excited CO ladders are found in all high luminosity/compact sources with an energetically dominant AGN (and only in those sources). 23

24 Water in molecular clouds H 2 O ice abundant in molecular clouds Can be released into the gas phase by UV photons, X-rays, cosmic rays, shocks,... Can be formed directly in the gas phase in warm molecular gas Abundant, many strong transitions expected to be major coolant of warm, dense molecular gas Herschel image of (part of) the Rosetta Molecular Cloud 24

25 H 2 O in Target log(l IR /L ) Mrk IRAS F IRAS Arp Mrk IRAS F Arp NGC IRAS F Arp IC NGC NGC NGC Target log(l IR /L ) IC 4687/ NGC NGC MCG Mrk IRAS NGC Zw NGC IRAS F NGC NGC NGC NGC red = wet 25

26 H 2 O lines in Mrk231 Low lines: pumping by cool component + some collisional excitation High lines: pumping by warm component Radiative pumping dominates and reveals an infrared-opaque ( 100 m ~ 1) disk. (González-Alfonso et al., 2010) 26

27 Lessons from H 2 O ( ) 1) In spite of high luminosities, H 2 O lines are unimportant for cooling the warm molecular gas. 2) Radiatively H 2 O lines reveal extended infrared-opaque circumnuclear gas disks. 3) Extinction and radiative pumping of highest CO lines. 4) Detection of H 2 O lines implies high FIR radiation field, but not the presence of an AGN. 27

28 Lessons from H 2 O (5) Radiation pressure from the strong IR radiation field: 4 P T / rad 100 d c Since both 100 and T d are high, radiation pressure dominates the gas dynamics in the circumnuclear disk. 5) Conditions in the circumnuclear molecular disk are Eddington-limited. 28

29 Mechanical feedback Radiation pressure can drive the observed molecular outflows (e.g., Murray et al., 2005) Aalto et al., 2012: flow prominent in HCN dense gas Key process in linking ULIRGs and QSOs? (Fischer et al., 2010) Shocks probably of minor importance in Mrk231 (Feruglio et al., 2010) 29

30 NGC6240: CO lines as tracers of what? X-ray nuclei AGNs? PAH emission PDRs? NB: FTS shows 12 CO/ 13 CO > 50! Optically thin CO lines H 2 lines shocks! 30

31 NGC253: shocks or PDRs? chemistry shocks? H 2 lines PDRs! SINFONI H 2 v=1 0 S(1), Rosenberg et al., in prep. 31

32 NGC7469 SPIRE FTS: CO ladder suggests PDR? 32

33 NGC7469 SPIRE FTS: OH + suggests XDR? 33

34 NGC7469 SPIRE FTS: OH + suggests XDR? But no H 2 O

35 High-z connection (1): H 2 O at z=3.9 Line ratios similar to Mrk231 FIR pumping dominates, implies 100 m-opaque disk Radiation pressure dominates, Eddington-limited Van der Werf et al.,