M82 Blue : Chandra Red : Spitzer Green & Orange : Hubble

1. Absorption-line probes of the prevalence and properties of outflows in the present-day star-forming galaxies? Chen, Y.-M.(UW-Madison/NJU), Tremonti, C., Heckman, T., Kauffmann, G., Weiner, B., Brinchmann, J., Wang, J. Face-on i = 0 Edge-on i = 90 Y i M82 Blue: Chandra Red: Spitzer Green &Orange:Hubble X

2. Outline • Background • Sample • Data analysis • Results

3. Outflow velocity vs. SFR

4. Outflow velocity vs. SFR Voff ~ SFR0.35 Martin 2005

5. Sample: SDSS DR7 star forming galaxies • 0.05<z<0.18 • r-band fracDeV<0.8 • D4000<1.5

6. Main steps of data analysis stellar Na D Absorption Disk-like（v=0） ISM outflow 1. stack spectra (i, Av, SFR, SSFR, M* ...) 2. subtract stellar contribution (CB08) 3. fit ISM absorption with two components

7. Stack spectrum and stellar continuum He I Mg I Na I

8. Two-component fit of ISM Na D • Line center shift: • outflow velocity Voff • Line strength (EW): • covering factor Cf • Line widthb • Line ratio τ0

9. Two-component fit of ISM Na D • Line center shift: • outflow velocity Voff • Line strength (EW): • covering factor Cf • Line widthb • Line ratio τ0

10. Inclination effect face on edge on

11. Isolate the main driver of the observed correlation: Disk-like components

12. Isolate the main driver of the observed correlation: outflow components

13. Outflow velocity vs. SFR Voff ~ SFR0.3

14. Summary • outflow is perpendicular to the disk and has an opening angle of ～60 degree • disk component is highly dependent on the dust extinction, and secondarily on SFR surface density • outflow component depends on SFR surface density strongly and secondarily on Av • we do not find the correlation between outflow velocity • and SFR from our sample, more observations on the low SFR end are needed

15. Thanks!

16. Background From optical absorption lines (Rupke et al. 2005a,b,c) • = Starbursts  = Seyfert 2s dwarf galaxies from Schwartz & Martin 2004

17. Background Outflow velocity vs. SFR

18. Martin et al. 2009 Spectra from LRIS on Keck I Using multi-components to fit each absorption line

19. Through the fitting in last slides, they find that components with different velocity have different covering factoroutflow is accelerating

20. From optical absorption lines—NaD(5890,5896A) (Rupke et al. 2005a,b,c) • Larger sample • New method for Fitting NaD • -- line shift  Velocity • -- doublet ratio Optical depth • -- line strength  covering factor

21. From optical absorption lines (Rupke et al. 2005a,b,c) isothermal escape speed Murray et al. 2004, Martin 2005 Outflow velocity Circular velocity Star formation rate

22. Martin et al. 2009 Spectra from LRIS on Keck I Using multi-components with different velocity to fit each absorption line

23. Outflows are ubiquitous in galaxies in which the global SFR per unit area exceeds roughly 0.1 solar mass per year per kpc^2 • (Heckman et al. 2002) • Are there any outflows in local normal star forming galaxies?

24. Two categories of the gas in a SF/SB galaxy wind • Ambient interstellar medium • Energetic fluid created by thermalization of the SB’s stellar eject • The hydrodynamical interaction between these two generates the multiphase starburst-driven galactic wind.

25. Observations of multiphase wind (cold, warm, hot gas & dust) • X-ray • Morphology and kinematics of interstellar emission lines (e.g. Ha…) • Outflow kinematics in the interstellar absorption lines (e.g. MgII, NaD)

26. From optical absorption lines--NaD(5890,5896A) Low- ionization potential 5.1eV (Martin et al. 2005, 2006) He I V = -435 km/s V = -96 km/s

27. Disk-like component

28. Outflow component

29. From X-ray: Hot Gas Escapes from Dwarf Starbursts Vc= 130 km/s Tremonti et al. 2004 Rotation Speed  Martin 1999, Heckman et al 2000, Martin 2004