the spectral energy distributions of narrow-line seyfert 1 galaxies

The Spectral Energy The Spectral Energy Distributions of Distributions of

Narrow-line Seyfert 1 Narrow-line Seyfert 1 GalaxiesGalaxies

Karen M. LeighlyKaren M. Leighly

The University of OklahomaThe University of Oklahoma

SummarySummary

The spectral energy distribution, as The spectral energy distribution, as either the either the originorigin or the or the consequenceconsequence, is key for , is key for understanding Narrow-line Seyfert 1 understanding Narrow-line Seyfert 1 galaxies.galaxies.

ASCA Observations of ASCA Observations of NLS1sNLS1s

Absolute accretion rate

Emission region size

~black hole mass

Leighly Leighly 19991999

Variance / Soft Excess Variance / Soft Excess CorrelationCorrelation

1H 0707-495

Ton S180

Leighly Leighly 19991999

AlphaAlphaxxxx is a measure of the is a measure of the strength of the soft excessstrength of the soft excess

1H 0707-495 Ton 1H 0707-495 Ton S180S180

z=0.04 z=0.04 XMM-Newton XMM-Newton

observation observation 10/200010/2000

Exposure ~ 40 ksExposure ~ 40 ks Boller et al. 2002Boller et al. 2002

Z=0.06Z=0.06 XMM-Newton XMM-Newton

observation observation 12/200012/2000

Exposure ~30 ksExposure ~30 ks Vaughan et al. Vaughan et al.

20022002

Andrea Crews, Carnegie Andrea Crews, Carnegie MellonMellon

Chiho Matsumoto, Chiho Matsumoto, OUOU

Spectral PropertiesSpectral Properties

Prominent soft excess.Prominent soft excess. Well modeled by a Well modeled by a

singlesingle blackbody blackbody

Subtle soft excessSubtle soft excess Modeled as two Modeled as two

Comptonized spectra Comptonized spectra by Vaughan et al.by Vaughan et al.

Light CurvesLight Curves

High varianceHigh variance Variance roughly Variance roughly

independent of energy.independent of energy.

Low varianceLow variance Variance roughly Variance roughly

independent of energy.independent of energy.

Structure Function Structure Function AnalysisAnalysis

2-10 keV structure 2-10 keV structure function appears function appears harderharder than other bands on short than other bands on short time scales.time scales.

3-10 keV structure 3-10 keV structure function appears function appears similarsimilar to other bands to other bands on short time scales.on short time scales.

Energy-sliced Light Energy-sliced Light CurvesCurves

Hard X-rays mirror soft X-rays Hard X-rays mirror soft X-rays loosely.loosely.

Hard X-rays show additional Hard X-rays show additional short time scale variabilityshort time scale variability

Implication: Implication: two physically two physically distinct componentsdistinct components

Hard X-rays and soft X-rays show Hard X-rays and soft X-rays show nearly identical variability.nearly identical variability.

Implication: Implication: components are not components are not distinct. distinct. Perhaps a distribution of Perhaps a distribution of optical depths and temperatures.optical depths and temperatures.

Chandra Chandra Observation of Observation of 1H 0707-4951H 0707-495

Hard X-rays much more Hard X-rays much more variable than soft X-rays.variable than soft X-rays.

Qualitatively similar to Qualitatively similar to behavior during XMM-behavior during XMM-Newton observation.Newton observation.

Also true in I Zw 1, in which Also true in I Zw 1, in which a hard flare was observed? a hard flare was observed? (See poster by Luigi Gallo)(See poster by Luigi Gallo)

Optical SpectraOptical Spectra

No profound differences between the optical No profound differences between the optical spectra, as expected.spectra, as expected.

John Moore, John Moore, OUOU

UV SpectraUV Spectra

Strong low-ionization linesStrong low-ionization lines High SiIII]/CIII] ratioHigh SiIII]/CIII] ratio Strongly blueshifted, low Strongly blueshifted, low

equivalent width CIV line.equivalent width CIV line.

Strong high-ionization linesStrong high-ionization lines Moderate SiIII]/CIII] ratioModerate SiIII]/CIII] ratio Weakly blueshifted, high Weakly blueshifted, high

equivalent width CIV.equivalent width CIV.

CIV in a Sample of NLS1sCIV in a Sample of NLS1s

Ton Ton S180S180

1H 0707-1H 0707-495495

Blueshifted Blueshifted lineline

Symmetric Symmetric lineline

An InterpretationAn Interpretation CIV line in some NLS1s is dominated by emission CIV line in some NLS1s is dominated by emission

in a in a windwind, resulting in the blueshift (red side is , resulting in the blueshift (red side is blocked by optically thick accretion disk). blocked by optically thick accretion disk).

What determines the presence of a wind?What determines the presence of a wind? The answer: The answer: the spectral energy distributionthe spectral energy distribution..

X-rays relatively X-rays relatively strong compared strong compared with UVwith UV

X-rays relatively X-rays relatively weak compared weak compared with UVwith UV

Resonance Line Driven Resonance Line Driven WindsWinds

What is required for a wind?What is required for a wind? Resonance scattering of UV photons Resonance scattering of UV photons

drives the wind, so the UV should be drives the wind, so the UV should be strongstrong..

X-rays can overionize the wind (e.g. X-rays can overionize the wind (e.g. Proga et al.), so X-rays should be Proga et al.), so X-rays should be weakweak..

So steep alphaSo steep alphaoxox should be associated should be associated with a wind.with a wind.

1H 0707-495 and Ton 1H 0707-495 and Ton S180S180

Low-Ionization LinesLow-Ionization Lines Low-ionization lines Low-ionization lines

(FeII, SiII) are strong (FeII, SiII) are strong in windy NLS1s.in windy NLS1s.

Filtering continuum Filtering continuum through the wind through the wind creates a much harder creates a much harder continuum that continuum that produces lines produces lines characterized by low characterized by low ionization potential.ionization potential.

Many details in Many details in Leighly & Moore (ApJ, Leighly & Moore (ApJ, submitted)submitted)

Also, next Tuesday-Also, next Tuesday-RIKEN, Wednesday-RIKEN, Wednesday-ISASISAS

Why do some NLS1s have blueshifted Why do some NLS1s have blueshifted lines?lines?

A A blueblue UV continuum and UV continuum and weakweak X-ray emission can X-ray emission can accelerate a wind without overionizing it. The wind accelerate a wind without overionizing it. The wind emits blueshifted high-ionization lines (CIV, NV, OVI). emits blueshifted high-ionization lines (CIV, NV, OVI).

The wind filters the continuum before it strikes the The wind filters the continuum before it strikes the intermediate-line emitting region. That region emits intermediate-line emitting region. That region emits rather low-ionization lines (FeII, MgII, SiII).rather low-ionization lines (FeII, MgII, SiII).

Why do some NLS1s not have Why do some NLS1s not have blueshifted lines?blueshifted lines?

Strong X-ray emission ionizes the wind Strong X-ray emission ionizes the wind before it can be accelerated. before it can be accelerated.

The unfiltered continuum illuminates disk The unfiltered continuum illuminates disk atmosphere producing strong relatively atmosphere producing strong relatively narrow and symmetric high-ionization lines. narrow and symmetric high-ionization lines.

Extreme NLS1s: RE Extreme NLS1s: RE 1034+391034+39

Simultaneous Simultaneous ASCA, EUVE, ASCA, EUVE, FUSE FUSE observationsobservations

A much A much harder harder continuum continuum than that of than that of 1H 0707-4951H 0707-495 Casebeer & Leighly, in

prep.Darrin Casebeer, Darrin Casebeer, OUOU

Emission lines in Emission lines in RE1034+39 can RE1034+39 can all be modelled all be modelled with nearly the with nearly the same profile - no same profile - no blueshifted blueshifted emission, as emission, as predicted.predicted.

Semi-empirical SED Semi-empirical SED modelingmodeling

Semi-Semi-empirical empirical spectral spectral energy energy distributions distributions parameterizeparameterized by cutoff d by cutoff temperature temperature

Modeling RE1034+39Modeling RE1034+39

Darrin looked for an Darrin looked for an SED consistent with SED consistent with the lines he the lines he measures. He measures. He concludes that he concludes that he very hard spectrum very hard spectrum is not only consistent is not only consistent but but required required to to produce the produce the observed equivalent observed equivalent widths and ratioswidths and ratios

PHL 1811 PHL 1811

SimultaneouSimultaneous HST and s HST and Chandra Chandra observationsobservations

Intrinsically Intrinsically X-ray weak - X-ray weak - no evidence no evidence for for significant significant absorptionabsorption

Leighly, Halpern & Jenkins in prep.

Intrinsically X-ray WeakIntrinsically X-ray Weak

Factor of 4 variability in 12 days Factor of 4 variability in 12 days - rules out scattered X-rays.- rules out scattered X-rays.

Nominal NLS1 photon index Nominal NLS1 photon index (2.25) plus black body - rules (2.25) plus black body - rules out absorptionout absorption

Ratio of the two spectra Ratio of the two spectra reveal evidence for reveal evidence for spectral variabilityspectral variability

12/17/01

12/05/01

No Evidence for No Evidence for AbsorptionAbsorption

No clear evidence for No clear evidence for intrinsic absorption on CIV - intrinsic absorption on CIV - small feature has equivalent small feature has equivalent width of 0.2 angstroms.width of 0.2 angstroms.

PHL 1811 is very unusual PHL 1811 is very unusual compared with other soft compared with other soft X-ray weak AGNsX-ray weak AGNs

Galactic

PHL 1811PHL 1811

CIV line is blueshifted, CIV line is blueshifted, as expected.as expected.

NV line may be NV line may be blueshifted also.blueshifted also.

Strong UV FeII in PHL Strong UV FeII in PHL 18111811

No semiforbidden or forbidden lines.No semiforbidden or forbidden lines.

Very low-ionization linesVery low-ionization lines

Strong NaD and CaII H&K linesStrong NaD and CaII H&K lines

X-ray Outflows in 1H X-ray Outflows in 1H 0707-4950707-495

Modeling done by Modeling done by Yair Krongold and Yair Krongold and Fabrizio Nicastro Fabrizio Nicastro (CfA).(CfA).

First component: First component: U=1.14 U=1.14 logNH=21.92 logNH=21.92 Vout=24,000 km/sVout=24,000 km/s

Second Second component: component: U=1.47 U=1.47 logNH=22.4 logNH=22.4 Vout=45,000 km/sVout=45,000 km/s

Also Pounds et al.Also Pounds et al.

SummarySummary The spectral energy distribution, as either the The spectral energy distribution, as either the

origin or the consequence, is key for origin or the consequence, is key for understanding Narrow-line Seyfert 1 galaxies.understanding Narrow-line Seyfert 1 galaxies.

NLS1 emission lines are a NLS1 emission lines are a consequenceconsequence of of the SED, both in their excitation and the SED, both in their excitation and dynamics.dynamics.

OriginOrigin of the SED is in the central engine. of the SED is in the central engine. Dispersion in X-ray spectral and variability Dispersion in X-ray spectral and variability properties among NLS1s indicates different properties among NLS1s indicates different conditions, geometries, …conditions, geometries, …

And so we attempt to approach a complete And so we attempt to approach a complete picture of NLS1s…picture of NLS1s…