Download presentation
Presentation is loading. Please wait.
Published bySpencer Robert Walton Modified over 8 years ago
1
SED of Galaxies in the IR–MM domain Frédéric Boone LERMA, Observatoire de Paris
2
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)
3
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
4
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)
5
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
6
● 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
7
Spitzer+ISO data (Rowan-Robinson et al 2005)
8
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
9
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
10
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
11
CO survey of water megamaser galaxies 24 galaxies detected in CO(1-0) and/or CO(2-1) 26 galaxies observed with IRAM 30m
12
CO survey of water megamaser galaxies
13
--> Dust in thermal equilibrium with molecular gas --> F(60 m) and F(100 m) from large scale galaxy disk From IRAS fluxes
14
CO survey of water megamaser galaxies 60K 20K AGN emission <25 m
15
CO survey of water megamaser galaxies AGN emission <25 m Rowan-Robinson 95
16
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
17
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
18
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
Similar presentations
© 2024 SlidePlayer.com Inc.
All rights reserved.