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Feedback: in the form of outflow. AGN driven outflow. M82 Blue : Chandra Red : Spitzer Cyan : Optical. Star formation driven outflow. Two categories of the gas in a SF/SB galaxy wind. Ambient interstellar medium
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M82 Blue: Chandra Red: Spitzer Cyan: Optical
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 Vc= 130 km/s Tremonti et al. 2004 Rotation Speed Martin 1999, Heckman et al 2000, Martin 2004
From optical absorption lines--NaD(5890,5896A) Low- ionization potential 5.1eV (Martin et al. 2005, 2006) V = -435 km/s V = -96 km/s
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
Stack spectrum and stellar continuum He I Mg I Na I
Two-component fit of ISM Na D • Line center shift: • outflow velocity Voff • Line strength (EW): • covering factor Cf • Line widthb • Line ratio τ0
Two-component fit of ISM Na D • Line center shift: • outflow velocity Voff • Line strength (EW): • covering factor Cf • Line widthb • Line ratio τ0
Inclination effect face on edge on
Isolate the main driver of the observed correlation: Disk-like components
Isolate the main driver of the observed correlation: outflow components
Outflow 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