Min-zhi Min-zhi KongKong

Physical Parameters Related to AGN

Variability ---- especially for

NGC 5548

outline

parameters of AGN variability

Observations and theoretical models for NGC 5548

Fitting the correlation between the variation of the optical spectral index and the continuum luminosity for NGC 5548

summary

Flux density variation of continuum or lines

I AGN variability parameters

(Ulrich et al. 1997)

(Kollatschny & Dietrich 1996)

NGC 4151

NGC 5548

continuum and line shape

(Ulrich et al. 1997)

Correlations

(Shapovalova et al. 2004)

High state

Low state

Time delay between variations at different continuum or lines

Variation time scale

(peterson et al. 2002)

ⅡⅡ Introduction for NGC5548Introduction for NGC5548

Observation for NGC 5548 in radio, infrared, UV, optical, X-ray ,γ-ray The flux of the continuum and line are variable, co

rrelated different time-delay existed Theoretical models

X-ray reprocessing mode (Mushotzky Done & Pounds 1993; Utterly et al. 2003;Chiang et al. 2002, 2003; Czerny et al. 1999;Molendi et al. 1992)

(Utterly et al. 2003)

A model from the spectral decomposition of the variable multi-wavelength continuum

(Magdziarz et al. 1998)

1) A cool multitemperature blackbody (dot-shot-dashed)

2) An EUV/soft x-ray component (short-dashed)

3) A hard thermal comptonized component (long-dashed)

The spectral index increasing with the monochromatic luminosity result from the radiation temperature changes of an emitting blackbody (Trevese et al. 2001; Kawaguchi et al. 1998)

(Trevese & Vagnetti 2001)

Ⅲ Ⅲ correlation of correlation of ααoptopt , L , L51005100 and fitting and fitting Continuum luminosity at 5100Å

http://www.astronomy.ohio-state.edu/~agnwatch

Host galaxy contributions : 3.4*10-15 ergs-1 Å-1 (Romainishin et al. 1995)

Galaxy extinction : 0.020 Redshift correction : 0.017

Optical spectral index ααoptopt Fit in line free regions 3700~3715Å, 3740~3800Å, 4041~4043Å, 4150~4250Å, 5550~5850Å, 6000~6290Å, 6400~6450 No considering host galaxy effect Wavelength range : ≥4000Å and ≥

6000Å

431 data points The coefficient is –0.8 The optical continuum

slope becomes flatter when it becomes more bright

The light curves for λLλ and αopt

140.5

3

33( ) 1

8inRGMM

T rr

1

122

3

rkTh

ec

hB

out

in

R

R rkTh

e

rdr

c

ihL

1

cos42

32

Accretion disk model Accretion disk model

The five free parameters

MBH=12.3×107Msun (Kaspi et al. 2000)

i=450 (Chiang et al. 2003; Wu & Han 2001)

Rout ~ 105Rs The possible mechanisms

, the accretion rate , the inner edge of the disk A co-variable mode

mARR sin /

minR

in out, i, R , R , MBHM

42 82 122 , 0.3

: 0.03 ~ 0.2in s s sR R R R

m

0.06 0.1 0.18, 0.38

: 205 ~ 19.6

m

R Rs

-/ , 0.28sinR R Am

in

12.5 0.8

m: 0.05~0.16,R : 55.5 ~ 133.9R s

A

Results

BC

A

A = 12.5 The accretion rate

ranges: 0.05~0.16 the inner radius of

the accretion disk changes: 133.9~55.5Rs

-/ sinR R Am

conclusionsconclusions

can fit the correlation between the optical index and continuum luminosity well

The accretion rate ranges: 0.05~0.16; the inner radius of the accretion disk changes: 133.9~55.5Rs

Consistent with the following works:

Support a physical phenomenon : for NGC55448, ADAF + SSD

2000) Czerny & ( /

1999) alet (Liu /

1995) alet z(Abramowic /

3.1

9.0

2

RozanskamRR

mRR

mRR

sin

sin

sin

0.8/ 12.5in sR R m

TThankhankss