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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
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