SED of Galaxies in the IR–MM domain Frédéric Boone LERMA, Observatoire de Paris

Motivations ● Photometric redshifts ● Understand how star formation / nuclear activity contribute to the FIR-MM ● Interpretation of mm observation of high-z galaxies with ALMA --> Star Formation History --> AGN evolution, Black Hole growth ● Estimate L FIR --> Mass of dust --> constrain reionization epoch --> interpretation of optical observations (gives the total extinction, Burgarella et al 2005)

Model components ● 'Cirrus' cold dust (<30K) illuminated by old stars or quiescent star formation (e.g. Boulanger & Perault 1988 for the MW, Cox et al 1986, Helou et al 1986 in normal galaxies) ● Starburst dust (>30K) heated by OB stars ● AGN dust emission in the Mid-IR (Barvainis 1987, Pier & Krolik 1992) ● Very high optical depth starbursts like Arp 220

Cold dust in Local Universe Galaxies ● ISO and bolometer arrays like SCUBA and MAMBO confirmed the existence of cold dust in spiral and IR luminous galaxies (Guélin et al 93, 95; Sievers et al 94; Sodroski et al 94; Neininger et al 96; Braine et al 97; Dumke et al 97; Alton et al 98, 01; Haas et al 98; Davies et al 99; Frayer et al 99; Papadopoulos & Seaquist 99; Xilouris et al 99; Haas et al 00; Dunne et al 01; Popescu et al 02; Spinoglio et al 02; Hippelein et al 03; Stevens et al 05) ● SCUBA Local Universe Galaxy Survey includes a sample of 81 optically selected galaxies (Vlahakis, Dunne and Eales 2005) --> M cold dust /M Warm dust = 1000x > than in IR selected galaxies --> New estimation of the Luminosity Function (2x IRAS LF)

Local Universe submm luminosity function Vlahakis, Dunne and Eales (2005) Cold dust in Local Universe Galaxies 2x higher when cold dust in normal galaxies is included

● Cirrus Starburst Arp220-like AGN Spitzer Wide-area InfraRed Extragalactic Survey (Rowan-Robinson et al 2005) --> new population of luminous cold dust cirrus --> SMM galaxies may not be all violent starbursts --> bimodal SF: quiescent vs active both undergoing evolution

Spitzer+ISO data (Rowan-Robinson et al 2005)

Model components ● 'Cirrus' cold dust (<30K) illuminated by old stars or quiescent star formation (e.g. Boulanger & Perault 1988 for the MW, Cox et al 1986, Helou et al 1986 in normal galaxies) ● Starburst dust (>30K) heated by OB stars ● AGN dust emission in the Mid-IR (Barvainis 1987, Pier & Krolik 1992, Menkova et al 02) ● Very high optical depth starbursts like Arp 220

Dust emission from AGN Rowan-Robinson 95 ● Clear contribution to IR SED (Miley et al 85, Edelson & Malkan 86) ● But difficult to disentangle from other contributions

CO survey of water megamaser galaxies (Boone, Henkel and Weiss 06) ● Water megamasers probe the torus at parsec scales (e.g. Henkel et al 04) ● Megamaser emission is very sensitive to viewing angle Greenhil et al 95

CO survey of water megamaser galaxies 24 galaxies detected in CO(1-0) and/or CO(2-1) 26 galaxies observed with IRAM 30m

CO survey of water megamaser galaxies

--> Dust in thermal equilibrium with molecular gas --> F(60  m) and F(100  m) from large scale galaxy disk From IRAS fluxes

CO survey of water megamaser galaxies 60K 20K AGN emission <25  m

CO survey of water megamaser galaxies AGN emission <25  m Rowan-Robinson 95

CO survey of water megamaser galaxies --> The redder the MIR emission the brighter the maser emission --> Could be diirect evidence of torus structure! (need more work) --> Constraint on the torus opacity and size

CO survey of water megamaser galaxies K12  m K --> Rmax/Rmin~100 -->  (9.7)~1 0° 90° 0° Fritz, Franceschini, Hatziminaoglou 2006 AGN emission <25  m

Conclusion ● Interpretation of high-z submm emission in terms of galaxy evolution and SF History requires accurate estimation of cold dust, recent results tend to modify the evolution gap between z~1 and now but sample still small ● APEX—LABOCA mapping of nearby galaxies + heterodyne to estimate contamination by CO(3-2) (Seaquist et al 05) and measure the gas/dust profile ● Combining IR+CO+H2O maser is an efficient way to isolate the AGN dust emission ● Torus structure confirmed + constraints on its physical parameters