Probing AGN Outflows with Probing AGN Outflows with VariabilityVariability

Smita MathurSmita MathurOhio StateOhio State

Collaborators: Yair Krongold, Fabrizio Nicastro, Anjali Gupta Nancy Brickhouse, Martin Elvis

Outburst in NGC 2617Outburst in NGC 2617

Seyfert 1.8 Seyfert 1.8 Seyfert 1 Seyfert 1

Swift monitoringSwift monitoring

+ XMM

Outflows are ubiquitousOutflows are ubiquitous

Seen in 50% of Seyfert galaxies.Seen in 50% of Seyfert galaxies.

NGC 3783 HST and FUSE

Kaspi +

Physical models of outflowPhysical models of outflow

Accretion disk winds: Accretion disk winds: Proga et al. Proga et al.

- - small physical scalesmall physical scale Winds off obscuring torus: Winds off obscuring torus: Krolik & Krolik &

KrissKriss

- on pc to 10s of pc scale - on pc to 10s of pc scale

Outflowing NLROutflowing NLR Host galaxy ISMHost galaxy ISM

Disk windsDisk winds

Elvis 2000

Proga +

AGN outflowsAGN outflows

UbiquitousUbiquitous Location, physical properties not well Location, physical properties not well

known until recentlyknown until recently Accretion disk winds?Accretion disk winds? Dependence on black hole mass/ Dependence on black hole mass/

Eddington luminosity ratioEddington luminosity ratio

What is the distance of the What is the distance of the absorber from the nucleus?absorber from the nucleus?

Proposals span a factor of > Proposals span a factor of > 10106 6

from accretion disk to Kpc from accretion disk to Kpc scalescale

narrow line regionnarrow line regionn R2

How to measure the How to measure the density?density?

Metastable absorption lines.Metastable absorption lines.

- He I- He I**, , C IIC II**, , C IIIC III* *

- low ionization lines : distinct - low ionization lines : distinct parameter parameter

spacespace

- Non-detection NOT constraining- Non-detection NOT constraining

VariabilityVariability

VariabilityVariability

Density Distance

There There cancan be variability due to be variability due to absorber crossing line of sight.absorber crossing line of sight.

ButBut

Absorber Absorber mustmust vary in responses to vary in responses to changes in ionizing continuum.changes in ionizing continuum.

Why is this a hard Why is this a hard measurement?measurement?

X-rays: Integration times too largeX-rays: Integration times too large

(one day = 86.4 ks)(one day = 86.4 ks)

UV: need many observations with UV: need many observations with dense time sampling dense time sampling lots of HST lots of HST orbitsorbits

XMM Observations of NGC XMM Observations of NGC 40514051

RGS RGS High resolution spectrum High resolution spectrum

EPIC EPIC Variability Variability

The Powerful UTAThe Powerful UTA

Time 104 s

0 2 10

Log U

Log U

Log c

ount

rate

Krongold et al. 2007

R (HIP) = 0.5-1.0 lt days. (2300-4600 RS)

R (LIP) = < 3.5 lt days. (< 15800 RS)

BH mass in NGC 4051 is 2 x 106 M⊙

The outflow is clearly The outflow is clearly compactcompact

……consistent with an accretion disk origin.consistent with an accretion disk origin.

Rule out various models:Rule out various models: - wind off torus edge - wind off torus edge (Krolik & Kriss)(Krolik & Kriss)

- continuous range of ionization - continuous range of ionization

parameter parameter (Ogle et al.)(Ogle et al.)

Mass & Energy outflow ratesMass & Energy outflow rates

HIP & LIP mass outflow rates: HIP & LIP mass outflow rates:

~ 1 x 10~ 1 x 10-4 -4 MM⊙ ⊙

yryr-1-1

c.f. accretion rate: ~ 5 x 10c.f. accretion rate: ~ 5 x 10-3 -3 MM⊙⊙ yr yr-1-1

Kinetic power released: ~10Kinetic power released: ~1038 38 erg/s erg/s

c.f. bolometric luminosity: 2.5 x 10c.f. bolometric luminosity: 2.5 x 1043 43

erg/serg/s

Energy injection rate in the surrounding medium is significantly smaller than that required by feedback models

ScannapiecoSilk

Observational evidence for Observational evidence for accretion disk winds is accretion disk winds is

scarcescarce

Short time-scale variability remains an unexplored region of the parameter space.

Sparse sampling naturally leads to Sparse sampling naturally leads to large radial distance.large radial distance.

Often radial distance is Often radial distance is assumedassumed to to be that with escape velocity = be that with escape velocity = outflow velocity. outflow velocity.

Distance derived from metastable Distance derived from metastable states is states is assumedassumed for high ionization for high ionization outflow. outflow.

……..But what about luminous ..But what about luminous quasars?quasars?

Dietrich et al. in prep.

L

Z

MergerMerger

SecularSecular

Seyferts are NOT scaled down Quasars

Future directionsFuture directions

Intra-day time resolved spectroscopyIntra-day time resolved spectroscopy X-ray: XMM advantageX-ray: XMM advantage

-- CCD and gratings-- CCD and gratings UV: HST COSUV: HST COS

-- exquisite sensitivity-- exquisite sensitivity

Discovery of relativistic Discovery of relativistic outflows in soft X-raysoutflows in soft X-rays

Robust detectionRobust detection

V ~ 0.1c

Gupta et al.2013

Magneto-hydrodynamic Magneto-hydrodynamic wind?wind?

Gupta et al.2013b

Stay tuned….Stay tuned….