Stellar & AGN Feedback in Galaxies

1. Stellar & AGN Feedback in Galaxies GLCW8 Columbus 2007

2. Evidence for Feedback(Self-limited Star Formation?) Krabbe et al astro-ph/0703804 Mb~3 M*~4

3. Inefficient Star Formation-Feedback?Kennicutt 1998 Implies same physics over 4 decades in gas

4. Evidence for Feedback: Winds- significant mass & momentum in cold gas e.g., Heckman et al. 00; Martin 04,05 M82 (Subaru)

5. Evidence for Feedback(self-limiting BH accretion?) Greene & Ho 05

6. Large-Scale Feedback Fabian et al (2006) Perseus Cluster

7. Large-Scale Feedback Fabian et al (2006) Perseus Cluster

8. Feedback Mechanisms • Energy Input • Stars (local) • SN • HII • Winds • AGN • Via Radiation • Jets (large scale) • Winds (Broad Absorption Line QSOs) • Momentum Input • Stars • SN • Radiation • AGN • Radiation

9. Radiation Pressure Feedback • Dust absorbs the radiation produced by starbursts or AGN • Dust collisionally coupled to the gas: mfp ~ 1 a0.1n1 pc • Starlight provides turbulent pressure support of ISM • Momentum-driven wind: V∞ ~ VcL/c @MWV∞ L ~ 10-3 M*c2 ~ MWV∞c ÞMW ~ M* • Efficient mechanism for blowing cold dusty gas out of a galaxy (i.e, couples to the phase of the ISM with most of the mass) · · · · ·

10. Terminal Velocity of Outflowing Cold Gas Hot gas inferred to have Vhot ~ 500 km/s independent of  Ram pressure in hot wind Vterm ~ Vhot ~ 500 km/s L ~ LEDD  Vterm ~  ULIRGs Dwarfs LIRGs Vterm ~ 2.5  ~ Vesc Data from Martin (2005)

11. The Maximum Luminosity of Starbursts

12. Black Holes • Efficient angular momentum transport in mergers can trigger BH growth and AGN activity • Dust present outside Rsub ~ 1 L1/246 pc • If L  LM, AGN can blow dusty gas out of its vicinity, controlling its own fuel supply 1/2

13. The Maximum Luminosity of Quasars  from width of OIII line in NLR

14. The Origin of the M- Relation? 1/2 • Inside Rsub ~ 1 L46 pc, dust destroyed • ‘Normal’ optically thin Eddington limit applies • With sufficient fuel supply, L ~ LEDD MBH • As BH grows, L  LM 4

15. Is the BH or Stellar Feedback Responsible for the Bulk of the Gas Removal? • L*=4fg4c/G seen; implies radiation limited (not BH limited) star formation rate • Winds are seen; if massive enough, Faber-Jackson follows. Not blown by AGN • BH is affected by  but not fg; fine tuning required to arrange for Faber-Jackson • See ongoing star formation in ellipticals (at low level)--no supression of star formation in situ • But AGN feedback likely restricts mass accretion from large radii

16. Feedback in Galactic Disks • Marginally Stable: • H/R~vT/vc roughly constant • Stars form in molecular gas • dN/dM~ M-1.8 => mass in big clouds • Most stars form in Giant Molecuar Clouds

17. Clumps and Star Clusters • IRDCs: dN/dM~M-1.97 (Simon et al. ApJ 2006) • Clumps: dN/dM~M-1.8 • Molecular Cloud Cores dN/dM~-1.7(Lada,Bally & Stark 1991) • Clusters: dN/dM~M-2 (Lada & Lada 2003) • => Most stars form in massive clusters

18. Carina • Mass GMC ~ 5x105 Solar masses • Radius GMC ~ 40pc • L=2.5x107 Lsun (~1041 erg/s) • 70% from Trumpler 16, 16% from Tr 14 • Rcl ~ 2pc • X-rays consistent with standard IMF

19. Clumps in Carina

20. Forces Acting In Carina • Inward • Self-Gravity of shell -GMsh(R) Msh(R)/R2 • Turbulent pressure 4r2vT2 • Ram pressure 4r2vsh2 • Outward • HII gas pressure • 4r2 nkT = 4r2 (3Q/4r3)1/2 kT • Radiation pressure (1+)L/c,  <1 • Jet ram pressure dM/dt vjet

21. Dynamical Model (1D)

22. Dynamical Model (1D)

23. Dynamical Model (1D)

24. Dynamical Model (1D)

25. Dynamical Model (1D)

26. Summary(Local Feedback) • Star formation is observed to be inefficient • Scaling relations imply a single mechanism • SN too late to halt SF in Starbursts/ULIRGS • HII helps in MW, not in ULIRGS • Stellar Winds seem ineffective • Radiation pressure on dust can work