Feedback:in the form of outflow

AGN driven outflow

M82Blue: ChandraRed: SpitzerCyan: Optical

Star formation driven outflow

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 or AGN

The hydrodynamical interaction between these two generates the multiphase starburst-driven galactic wind.

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)

From X-ray: Hot Gas Escapes from Dwarf Starbursts

Martin 1999, Heckman et al 2000, Martin 2004

Rotation Speed Tremonti et al. 2004

Vc= 130 km/s

From optical absorption lines--NaD(5890,5896A)Low- ionization potential 5.1eV(Martin et al. 2005, 2006)

V = -96 km/s

V = -435 km/s

Circular velocity Star formation rate

Ou

tflo

w v

eloc

ity

isothermal escape speed

From optical absorption lines (Rupke et al. 2005a,b,c)

Murray et al. 2004, Martin 2005

Stack spectrum and stellar continuum

Mg I

He I

Na I

Two-component fit of ISM Na DTwo-component fit of ISM Na D

• Line center shift: outflow velocity Voff

• Line strength (EW): covering factor Cf • Line width b

• Line ratio τ0

Two-component fit of ISM Na DTwo-component fit of ISM Na D

• Line center shift: outflow velocity Voff

• Line strength (EW): covering factor Cf • Line width b

• Line ratio τ0

Inclination effectInclination effect

face on

edge on

Isolate the main driver of the observedcorrelation: Disk-like components

Isolate the main driver of the observedcorrelation: outflow components

Outflow velocity vs. SFROutflow velocity vs. SFR

Voff ~ SFR0.3

Martin et al. 2009

Spectra from LRIS on Keck I

Using multi-components to fit each absorption line

Through the fitting in last slides, they find that components with different velocity have different covering factoroutflow is accelerating