Observations and Physical Parameters Leah Simon Feb. 3, 2006 AGN OUTFLOWS Observations and Physical Parameters Leah Simon Feb. 3, 2006

Absorption: Types Unassociated/Associated: Redshift relative to quasar emission lines Intrinsic/Extrinsic: Ejected from Quasar or part of host galaxy OR external to quasar Broad Absorption Lines(BALs)/Narrow Absorption Lines(NALs) (mini-BALs): line widths FWHM Outflows come from Intrinsic Lines of all types Outflows occur in ~ 50% of all quasars!

Quasar Spectrum Rodriguez-Hidalgo, private communication

BALs V (FWHM)> 3000 km/s Redshifts from quasar up ~0.2c -> winds! HiBALS: high ionizations species CIV, NV, SiIV LoBALS: low ionization species CII, MgII,

NALs V spread (FWHM)< 100-200 km/s CIV doublet resolvable V shift < 5000 km/s -> associated (probably part of quasar/host)

Intrinsic Absorption: Strong Indicators BALs Large velocity widths Within ~60,000km/s of quasar redshift Variability: timescales of ~year(s) Caused by continuum source variability affecting photoionized clouds Or caused by cloud (outflow) motion across LOS Partial coverage Continuum source is small! Cloud must be nearby if some continuum source can pass around cloud to our eye

Variability Rodriguez-Hidalgo, private communication

Partial Coverage Barlow, Hamann, Sargent, 1997

Partial Coverage Cont. Hamann, Sabra, 2004

Intrinsic Absorption: Weaker Indicators Chemical signatures Fine structure lines place density limits -> intrinsic systems (probably) have higher densities Requires low ionizations – not observed often High Ionization and/or Metallicity - N(NV)/N(HI) Line profiles: broad and smooth Statistics: over-density of low-z (w/respect to quasar) NALs implies these are intrinsic Properties observed in intrinsic NALs appear correlated with quasar properties (radio loudness, L etc.

Physical Parameters of Outflows Column density ~1022 – 1025 cm-3 Velocity: 0 < v < 0.2c Mass loss rate roughly correlated with line strengths Mass loss due to line driving: Physical scale: calculate small region, however variability not observed on short enough time scales (~months) – something else is at work Abundances and ionization levels

Uncertainties in Interpretation Orientation Angle Possibly degenerate with age+evolution Needed to understand physical environment of QSO! Age + Evolution Shorter lifetimes allow a mixture of ages, evolutionary states at any given redshift Lifetimes Duty Cycle? Shielding/self shielding Uinner nγ/n ~ 5 – 10 Set such that gas at inner edge of wind is at ionizations low enough to be pushed by UV flux (Murray + Chiang, 1995)

Acceleration Mechanisms Radiation Pressure (Photoionization) Line Driving – momentum from radiation field through line opacity Expect vtransverse = small Require very high L/LEdd Thermal Pressure (Parker Wind) Not strong enough Requires Isothermal wind... Magnetic Pressure (Magnetocentrifugal Driving) 'Beads on a string' See John Everett (CITA)

Comparison to BH accretion Probably Mdotoutflow ~ Mdotaccretion Mass loss rate from accretion : Lacc= η Mdot c2 Mass loss rate in winds: Very uncertain!

References 1)T.A. Barlow, F. Hamann, W.L.W. Sargent, 1997 astro-ph/9705048 2)D.M. Crenshaw, S.B. Kraemer, I.M. George, 2003 ARAA, 41:117 3)F. Hamann, B. Sabra, 2003 astro-ph/0310668 4)N. Murray, J. Chiang, 1995 ApJ 454: L105 5)N. Murray, J. Chiang, S.A. Grossman, G.M. Voit, 1995 ApJ 451: 498 6)D. Proga, J.M. Stone, T.R. Kallman, 2000 ApJ 543: 686 7)M. Urry, P. Padovani, 1995 PASP 107:803 8)R.J. Weymann, R.F. Carswell, M.G. Smith, 1981 ARAA, 19:41