Large-Scale Winds in Starbursts and AGN David S. Rupke University of Maryland Collaborators: Sylvain Veilleux D. B. Sanders  v = km s -1 Rupke, Veilleux, & Sanders 2005a,b,c, submitted

DensityTemperature Cooper, Bicknell, & Sutherland 2005, in prep., and... Veilleux, Cecil, & Bland-Hawthorn 2005, ARAA, in press

Sample 78 starbursts –50% luminous infrared galaxies (L IR > L  ) –50% ultraluminous infrared galaxies (L IR > L  ) 26 AGN –mostly Seyfert 2 ULIRGs –a few Seyfert 1s 104 total galaxies!  the largest superwind survey to date at z < 3

Method Spectroscopy of the Na I D doublet –Moderate resolution km s -1 –Data from Keck II (10m), MMT (6.5m), KPNO (4m) Fit absorption lines –multiple velocity components –Gaussians in optical depth –yields velocity, Doppler parameter, optical depth, covering fraction Compute –Mass, Momentum, Energy, and their outflow rates –*Simple model of constant-velocity, mass-conserving wind (* Model assumes thin shell, time-averaged outflow rates)

Detection rates Comparison of different subsamples –starburst LIRGs45% (± 10%) –Seyfert 2 ULIRGs45%(± 10%) –starburst ULIRGs70 – 80%(± 10%) Differences in detection rate appear to reflect GEOMETRY –wind opening angle for moderate starbursts and Seyfert 2s in local universe is C Ώ ~  there are winds in all starburst LIRGs and Seyfert 2 ULIRGs! Same conclusion applies to ULIRGs

Velocities  V(LIRG)  <  V(SB ULIRG)  <  V(Sy2 ULIRG)  100 km/s < 170 km/s < 220 km/s  V(H II)  <  V(LINER)  <  V(Sy2)  120 km/s < 230 km/s < 310 km/s Spectral Type Star Formation rate / Nuclear Activity } significant

AGN- vs. Starburst-driven winds? Can we demonstrate that AGNs help drive winds in Seyfert ULIRGs? –No! The statistics don’t convincingly indicate it. –But there are hints... Seyfert 2 ULIRGs are statistically indistinguishable from SB ULIRGs –however, the SFRs and outflow detection rates are lower in Seyfert 2 ULIRGs than in SB ULIRGs –So differences between Sy2 ULIRGs and LIRGs may imply an AGN contribution.

Circular velocityStar formation rate Outflow velocity isothermal escape speed  = Starbursts  = Seyfert 2s Outflow properties vs. Galaxy properties dwarf galaxies from Schwartz & Martin 2004 Murray et al. 2004, Martin 2005

Circular velocityInfrared luminosity Mass outflow rate Starburst99 prediction (t SB > 40 Myr, Z = Z  )  = Starbursts  = Seyfert 2s

Circular velocity Infrared luminosity Momentum outflow rate SB99  = Starbursts  = Seyfert 2s Radiation pressure

Circular velocityInfrared luminosity Energy outflow rate SB99  = Starbursts  = Seyfert 2s

Slopes of Correlations Strong dependence on galactic mass –velocity, mass, momentum, and energy all increase sharply with circular velocity –Power-law slopes of 3-5 ! Linear dependence of mass, momentum on SFR –but energy increases more sharply as SFR increases  increase in thermalization efficiency with SFR? –v  SFR 0.2 Metallicity effects –incorporating the K-band L–Z relationship (Salzer et al. 2005) does not change these conclusions significantly –I.e. metallicity is not driving these trends! (preliminary)

Correlations at SFR  100 M  yr -1 We observe a statistically significant flattening in dependence of outflow properties on galaxy properties. Possible explanations: –depletion of gas reservoirs –decrease in thermalization efficiency –velocity ceiling (Murray et al. 2004, Martin 2005) –saturation in star formation surface density (Strickland et al. 2004a,b)

[O III] [N II] Na I D model  V max (ionized)  V max (neutral)

Neutral/Ionized Correlations FWHM [O III] 5007 Na I D velocity All galaxies Galaxies with BELA

Mrk 231 – AGN + Starburst winds? A Seyfert 1 ULIRG Small-scale AGN outflow observed in Na I D –broad, high-velocity (  v = 4000 – 8000 km s -1 ) absorption (e.g., Boksenberg et al. 1977) –highest velocity component is variable A large-scale outflow observed –blueshifted emission lines (Hamilton & Keel 1987) –blueshifted absorption lines (  v  2000 km s -1 ) Jet or wide-angle outflow? –disk geometry and measured velocities favor wide-angle outflow –however, jet could still inject energy...

blueshifted Na I D v sys Nuclear offset (kpc) 4 kpc Heliocentric velocity

Summary/Outlook Winds occur in ~ all LIRGs and ULIRGs Can’t yet convincingly demonstrate influence of AGNs on large-scale outflow –need more data on Seyfert 2s –there are hints Outflow and galaxy properties are strongly correlated –flattening at high SFR, galaxy mass Ionized and neutral gas is correlated –V max (ionized)  V max (neutral) Mrk 231 is a good example of a galaxy with both a small- and a (spatially-resolved!) large-scale wind.