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Extragalactic jets: a new perspective. G. Ghisellini in coll. with F. Tavecchio INAF-OABrera. Almost every galaxy hosts a BH. 99% are silent 1% are active 0.1% have jets. FRI-FRII & Blazars. Blazars: Spectral Energy Distribution. Radio IR Opt UV X MeV GeV.
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Extragalactic jets: a new perspective G. Ghisellini in coll. with F. Tavecchio INAF-OABrera Almost every galaxy hosts a BH 99% are silent 1% are active 0.1% have jets
Blazars: Spectral Energy Distribution Radio IR Opt UV X MeV GeV Inverse Compton (also possible hadronic models) Synchro
The“blazarsequence” FSRQs BL Lacs LBL and HBL Fossati et al. 1998; Donato et al. 2001
gpeaknB 2 Fossati et al. 1998; Donato et al. 2001
By modeling, we find physical parameters in the comoving frame. gpeak is the energy of electrons emitting at the peak of the SED TeV BL Lacs EGRET blazars
Low power slow cooling large gpeak Big power fast cooling small gpeak
The power of blazar jets G Lr = radiation Le = relat. electrons Lp = protons LB = B-field R Rdiss ~1017 cm
Ghisellini, Foschini, Tavecchio, Pian 2007 AGILE! 3C 454.3 Swift
High power If one p per e- Relat. electrons Celotti & Ghisellini 2007 Powerful jets are not magnetically dominated Magnetic Field Radiation Celotti GG 2008
Jet power vs disk Lum. GRBs BL Lacs, FSRQ, mQSO Photon trapping LdiskPjet e-p decoupling Disk accretion rate (Eddington units)
Pause • Jet power is large. More than Ldisk • Matter dominated. Not many pairs • LB is small • Powerful jets must be radiatively inefficient • Powerful jets do not decelerate
A new blazar sequence • Old one: based on 1 parameter: the observed luminosity • Now: info on mass and accretion rate (spin? not yet) • Info on jet power vs disk luminosity • Info on location of dissipation: must be at some distance from BH. One zone is dominant (internal shocks?)
The key ideas 1/2 • Rdiss proportional to MBH • RBLR proportional to (Ldisk) UBLR=cost • For Ldisk/LEdd < Lc no BLR (BL Lacs)
Ledlow & Owen Ghisellini & Celotti 2001
The key ideas 1/2 • Rdiss proportional to MBH • RBLR proportional to (Ldisk) UBLR=cost • For Ldisk/LEdd < Lc no BLR (BL Lacs) • LB = eB Pjet B propto R-1 • Le = ee Pjet
LB = eB Pjet B propto R-1 • Le = ee Pjet Celotti & Ghisellini 2008
The key ideas 1/2 • Rdiss proportional to MBH • RBLR proportional to (Ldisk) UBLR=cost • For Ldisk/LEdd < Lc no BLR (BL Lacs) • LB = eB Pjet B propto R-1 • Le = ee Pjet • gpeak propto U-1; U-1/2
The key ideas 1/2 • Rdiss proportional to MBH • RBLR proportional to (Ldisk) • For Ldisk/LEdd < Lc no BLR (BL Lacs) • LB = eB Pjet • Le = ee Pjet • gpeak propto U-1; U-1/2 The key ansatz • Pjetalways proportional to M
M Ljet propto Ldisk M2 1/2 Ljet propto Ldisk ADAF (Narayan et al.)
Simple consequences • Rdiss propto M; RBLR propto (Ldisk)1/2 Low M, High L Red quasar BLR High M, Low L Blue quasar
Simple consequences • Small M, small Ljet, large B, red UBLR ~ the same BLR Large UB
Give me MBH and Ldisk (or LBLR) and I will tell you the SED of the jet and its power
Conclusions • Pjet > Ldisk • Jets are matter dominated • Link between M, M and observed SED • “Blue” FSRQs may exist • “Red” low power FSRQs may exist • Implications about evolution • GLAST + Swift + M + Ldisk (or LBLR)
AGILE GLAST Fossati et al. 1998; Donato et al. 2001 CT Swift
AGILE GLAST Fossati et al. 1998; Donato et al. 2001 CT Swift
Low power If one p per e- Relat. electrons Celotti & Ghisellini 2007 Magnetic Field Radiation
Subluminal motion for all TeV sources? Piner, Pant & Edwards 2008
Cospatial fast spine & slow layer 1015 cm DRl~1016 cm DRs~1014 cm
More seed photons for both • G’ = GlayerGspine(1-blayerbspine) • The spine sees an enhanced Urad coming from the layer • Also the layer sees an enhanced Urad coming from the spine • The IC emission is enhanced wrt to the standard SSC model
BL Lac Radiogalaxy
spine layer Ghisellini Tavecchio Chiaberge 2005 Tavecchio Ghisellini 2008
Coordinated variability at different n Mkn 421 TeV PDS MECS LECS
G=10-20 Dissipation here? Yes! ~1017 cm RBLR~1018cm Leptonic models: Maraschi Ghisellini Celotti 1992 Dermer Schlickeiser 1993 Sikora Begelman Rees 1994 Blandford Levinson 1995 Ghisellini Madau 1996 Dissipation here? NO! But see e.g.: Mannheim 1993; Aharonian 2002; Rachen 2000 for proton models
Importance of g-rays If g-g important too many X-rays dx,g>1 (>10) Rblob large enough (>1016 cm), but tvar<1day Rblob <2.5x1015 tvard cm Blob away from accretion disk X-ray corona (>1017 cm) Energy transport in inner jet must be dissipationless