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Extragalactic jets: a new perspective

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

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  1. 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

  2. FRI-FRII & Blazars

  3. Blazars: Spectral Energy Distribution Radio IR Opt UV X MeV GeV Inverse Compton (also possible hadronic models) Synchro

  4. The“blazarsequence” FSRQs BL Lacs LBL and HBL Fossati et al. 1998; Donato et al. 2001

  5. gpeaknB 2 Fossati et al. 1998; Donato et al. 2001

  6. 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

  7. Low power slow cooling large gpeak Big power fast cooling small gpeak

  8. Power of jets in blazars

  9. Power of jets in blazars

  10. Power of jets in blazars

  11. The power of blazar jets G Lr = radiation Le = relat. electrons Lp = protons LB = B-field R Rdiss ~1017 cm

  12. Ghisellini, Foschini, Tavecchio, Pian 2007 AGILE! 3C 454.3 Swift

  13. High power If one p per e- Relat. electrons Celotti & Ghisellini 2007 Powerful jets are not magnetically dominated Magnetic Field Radiation Celotti GG 2008

  14. Celotti GG 2008, Maraschi et al. 2008

  15. Jet power vs disk Lum. GRBs BL Lacs, FSRQ, mQSO Photon trapping LdiskPjet e-p decoupling Disk accretion rate (Eddington units)

  16. 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

  17. 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?)

  18. The key ideas 1/2 • Rdiss proportional to MBH • RBLR proportional to (Ldisk) UBLR=cost • For Ldisk/LEdd < Lc no BLR (BL Lacs)

  19. Ledlow & Owen Ghisellini & Celotti 2001

  20. 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

  21. LB = eB Pjet B propto R-1 • Le = ee Pjet Celotti & Ghisellini 2008

  22. 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

  23. 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

  24. M Ljet propto Ldisk M2 1/2 Ljet propto Ldisk ADAF (Narayan et al.)

  25. Simple consequences • Rdiss propto M; RBLR propto (Ldisk)1/2 Low M, High L Red quasar BLR High M, Low L Blue quasar

  26. Simple consequences • Small M, small Ljet, large B, red UBLR ~ the same BLR Large UB

  27. Give me MBH and Ldisk (or LBLR) and I will tell you the SED of the jet and its power

  28. 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)

  29. AGILE GLAST Fossati et al. 1998; Donato et al. 2001 CT Swift

  30. AGILE GLAST Fossati et al. 1998; Donato et al. 2001 CT Swift

  31. Low power If one p per e- Relat. electrons Celotti & Ghisellini 2007 Magnetic Field Radiation

  32. TeV BL Lacs

  33. Subluminal motion for all TeV sources? Piner, Pant & Edwards 2008

  34. Cospatial fast spine & slow layer 1015 cm DRl~1016 cm DRs~1014 cm

  35. 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

  36. BL Lac Radiogalaxy

  37. spine layer Ghisellini Tavecchio Chiaberge 2005 Tavecchio Ghisellini 2008

  38. Power of jets

  39. Coordinated variability at different n Mkn 421 TeV PDS MECS LECS

  40. 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

  41. 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

  42. Ravasio et al. 2000

  43. Fossati et al. 1998

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