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The disk-jet link: X-ray and radio monitoring of PKS 0558-504. Mario Gliozzi (GMU) I. Papadakis (Crete) W. Brinkmann (MPE) L. Kedziora-Chudczer (Sidney). *Disk-jet connection *AGN-GBH analogy *PKS 0558-504 in Grand Unification Model - PowerPoint PPT Presentation
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The disk-jet link:X-ray and radio monitoring of PKS 0558-
504
Mario Gliozzi (GMU)I. Papadakis (Crete) W. Brinkmann
(MPE) L. Kedziora-Chudczer (Sidney)
*Disk-jet connection*AGN-GBH analogy *PKS 0558-504 in Grand Unification Model *Results from RXTE & radio monitoring *Conclusions & future work
Disk & Jet
*Basic Ingredients of BH systems: Most evident manifestations of BH presence
*Growing evidence (theory, observations, simulations) of strong accretion-ejection link: No jet without accretion but not vice versa
*Main Goals:1) Understand the conditions leading to jet formation/quenching2) Assess jet role in energetics of the system
X-ray & Radio monitoring
Same phenomena occur on different scales: analogy GBHs -AGN
Previous studies demonstrate crucial role of radio X-ray monitoring:X-rays track the accretion activityRadio tracks the jet activity
Microquasar GRS1915+105 [Mirabel et al. 1998]
BLRG 3C120 [Marscher et al. 2002]
Grand Unification Model
2 main spectral states: 1) Low/Hard State (LS) and 2) High/Soft State (HS)
GBHs scaled down versions of AGN:AGN classes correspond to GBHs in different spectral states [e.g., Mc Hardy et al. 2006]
LS energy spectrum:
E [keV]
[Fig from Zdziarski & Gierlinski 2004]
HS energy spectrum:
E [keV]
Grand Unification Model
2 main spectral states: 1) Low/Hard State (LS) and 2) High/Soft State (HS)
GBHs scaled down versions of AGN:AGN classes correspond to GBHs in different spectral states [e.g.,Mc Hardy et al. 2006]
LS power spectrum: HS power spectrum:
[GX 339-4 Homan & Belloni 2004]
Grand Unification Model
2 main spectral states: 1) Low/Hard State (LS) and 2) High/Soft State (HS)
GBHs scaled down versions of AGN:AGN classes correspond to GBHs in different spectral states [e.g.,Mc Hardy et al. 2006]
LS radio properties: HS radio properties:
Persistent radio emissionCorrelation with X-rays: LR~LX
0.7
Emission from compact jet
[Fender et al. 2004; E. Gallo et al. 2004;]
Weak/absent radio emissionJet quenching
[Cyg X-1 Sterling et al. 2001]
GBH Intermediate State
HID: model-independent way to describe GBH evolutionExistence of Intermediate spectral State (IS)
IS energy spectrum:
[Fig from Zdziarski & Gierlinski 2004]
[GX 339-4 Homan & Belloni 2004]
GBH Intermediate State
HID: model-independent way to describe GBH evolutionExistence of Intermediate spectral State (IS)
IS power spectrum:
[Fig from Homan & Belloni 2004]
GBH Intermediate State
HID: model-independent way to describe GBH evolutionExistence of Intermediate spectral State (IS)
IS radio properties:
Transient & strong radio emissionSteep spectrumLarge bulk Lorentz factorMost powerful jet ejections
[GRS1915+105 Mirabel & Rodriguez 1998]
AGN-GBH Correspondence
IS requirements: * high accretion rate* strong radio emission* steep energy spectrum* PSD with QPOs
LS LLAGN Based on generalization of HID [Koerding et al. 2006]
Based on “fundamental plane” [Merloni et al. 2003; Falke et al. 2004]
HS Seyfert 1 Based on PSD [Uttley et al. 2002; Markowitz et al. 2003; McHardy et al. 2006]
IS ?
Importance of finding IS-analog AGN: frozen look of BH systems during major ejections
PKS 0558-504
Radio-loud: R~30 [Siebert et al. 1999]
BH mass: MBH~4x107 Msolar [Wang et al. 2001]
X-rays: Bright, Steep PL (Г~2.2), Variable [Gliozzi et al. 2007] Extremely variable: 67% flux variation in 3’ [Remillard et al. 1991]
In principle any radio-loud NLS1 satisfies basic requirements for IS,
but only few of these objects [Komossa et al. 2005]
only PKS 0558-504 bright enough for RXTE monitoring(F2-10 keV ~ 2x10-11 erg cm-2 s-1, L2-10 keV ~ 1045 erg s-1)
Requirements for IS
High accretion rate?
Jet radio emission?
Lbol ~ LEdd
Even considering MBH~ 5 Mvirial [Marconi et al. 2008]
and different bolometric corrections [Vasudevan & Fabian 2007]
Yes
Maybe (wait and see)
PSD with QPO?
No (at least not yet)Answer after XMM AO7
5 orbits (660ks PI Papadakis)
Energy spectrum match?
Comptonization [O’Brien et al. 2001; Brinkmann et al. 2004]Ionized Reflection [Ballantyne et al. 2001; Crummy et al. 2006]SLIM disk [Haba et al. 2008]Beamed emission [Remillard et al. 1991; Gliozzi et al. 2001]
Maybe (but spectral degeneracy)
Additional diagnostics for IS
From model-independent studies of spectral variability:
1) Fractional variability flattens in IS from LS to HS [Gierlinski & Zdziarski 2005]
E [keV]
LS HSIS
2) Short-term variability Cyg X-1 during IS characterized large flux changes without spectral variations
[Malzac et al. 2006]
RXTE monitoring of PKS 0558-504
Campaign:Started in March 2005;monitoring campaign under way
Sampling: 1 observation every 2 days+ 3 periods of denser coverage (2 observations per day)[Gliozzi et al. 2007]
Soft [2.5-5 keV] andHard [5-15 keV] fluxeshighly variable on day-monthtimescales.
Flux variability accompaniedby weak spectral variability.
Flux-Flux PlotPlot Hard [5-15 keV] versus Soft [2.5-5 keV] count rate to characterize the spectral variability [e.g., Churazov et al. 2001; Taylor et al. 2003] .
Two possible scenarios:1) If power-law trend: Spectral variability explained by pivoting. 2) If linear trend: Constant spectral shape with 2 components [Zdziarski et al. 2002]
Linear trend
Intercept = 0
no spectral pivoting
no contribution from hard component
Common physical origin for Soft & Hard
Fvar- E Plot
Plot Fractional variability Fvar vs energy
Fvar=√(S2- <σerr2>)/<x>
Different from typical jet-dominated behavior: Fvar α E[Gliozzi et al. 2006]
Mrk 501
Constant trend reminiscent of GBHs in IS[Gierlinski & Zdziarski 2005]
HR-ct Plot
Plot of hardness ratio HR=[5-15 keV]/[2.5-5 keV] vs. count rate Constant trend reminiscent of Cyg
X-1in IS[Malzac et al. 2006]
Different from typical jet-dominated
behavior: HR α ct[Gliozzi et al. 2006]
Mrk 501
Radio Observations
ATCA Imaging:18 GHz
F.O.V= 9”x13” beam=0.5”
(1”=2.4 kpc)
Source unresolved
Radio Observations
ATCA Imaging: 8.6 GHz
F.O.V= 18”x27” beam=1”
(1”=2.4 kpc)
2 symmetric lobes resolved(d=14 kpc)
Radio Observations
ATCA Imaging: 4.8 GHz
F.O.V= 38”x58” beam=2”
(1”=2.4 kpc)
2 symmetric lobes resolved(d=14 kpc)
Radio Observations
VLBI Imaging [S. Tingay]
jet resolved(R~100 pc)
Radio Monitoring
Radio emission highly variable
Timescales longer compared to X-rays
No trivial correlation with X-rays
but longer baseline needed
PKS 0558-504 IS-analog ?
High accretion rate?
Jet radio emission?
Energy spectrum match?
Yes
Yes
Typical Spectral variability?
Yes
PKS 0558-504 extraordinary object:high accretion rate AGN with strong radio jet,very bright, highly variable on all timescales.
Maybe: no evidence for reflection
Future Work
- From September 2008 PKS 0558-504 weekly monitored with SWIFT in Optical, UV, and soft X-ray to complement hard X-rays (RXTE) and hopefully radio monitoring.
-5 XMM-Newton orbits in AO7 for deep investigation of PSD (QPOs) and breaking spectral degeneracy via time-resolved spectroscopy.
- Further VLBI observations to investigate possible changes in the inner jet structure.