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Relativistic extragalatic jets

Relativistic extragalatic jets. Gabriele Ghisellini. Almost every galaxy hosts a BH. 99% are silent 1% are active 0.1% have jets. FRI-FRII & Blazars. Back to 1980s. COS-B. Blandford & Konigl 1979; Marscher 1980; Konigl 1981; Ghisellini, Maraschi Treves 1985. SSC. Synchro.

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Relativistic extragalatic jets

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  1. Relativistic extragalatic jets Gabriele Ghisellini Almost every galaxy hosts a BH 99% are silent 1% are active 0.1% have jets

  2. FRI-FRII & Blazars

  3. Back to 1980s COS-B Blandford & Konigl 1979; Marscher 1980; Konigl 1981; Ghisellini, Maraschi Treves 1985 SSC Synchro inhomogenous jets

  4. 1990s: EGRET

  5. 1990s: WHIPPLE

  6. TeV BL Lacs EGRET: ~60 blazars Cherenkov: ~6 BL Lacs GLAST The Universe becomes opacque at z~0.1 at 1TeV at z~2 at 20 GeV HESS+ MAGIC

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

  8. 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

  9. 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

  10. Theblazarsequence Fossati et al. 1998; Donato et al. 2001 5@5 GLAST

  11. Theblazarsequence npeakgpeak 2 ∞ Synchro InverseCompton Fossati et al. 1998; Donato et al. 2001

  12. By modeling, we find physical parameters in the comoving frame. gpeak is the energy of electrons emitting at the peak of the SED EGRET blazars

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

  14. tcool 1/(gpeak U) = R/c µ 2 ggpeakU = const µ

  15. Rees 1978 for M87 Observed time: (R0/c)G2(1-bcosq) ~ R0/c !

  16. 3C 279 Spada et al. 2001

  17. Mkn 421 Guetta et al. 2004

  18. Ghisellini 1999, Spada et al. 2001; Guetta et al. 2004

  19. Blandford 2002, 2003, Lyutikov 2003

  20. What carries the energy? e-p or e+e- or B? Power of jets first

  21. Power of jets in blazars

  22. Power of jets

  23. Power of jets in blazars

  24. Chandra jets 0637-752

  25. IC/CMB Synchrotron gmin~20 Sambruna et al.2002,2004, Tavecchio et al. 2000, 2004, Celotti et al. 2001; Schwartz G~10 P~1047-1048 erg/s Alternatives: Dermer & Atoyan 2002; Aharonian 2002; Stawarz et al. 2004; Harris et al. 2004

  26. Power of jets in blazars

  27. Protons (1 proton per emitting e-) Relat. Electrons B-field Radiation Cold elecrons Celotti & GG in prep

  28. If jet is matter dominated and fast from the beginning, it Comptonizes the radiation from the accretion disk...

  29. Protons or Poynting? • Pairs can outnumber protons, but are not dynamically important (Sikora et al. 2005) • Large Lic/Lsyn seems to favor protons • But no signs of bulk Compton… • Constraints are more severe for powerful jets

  30. Jet vs disk power GRBs Blazars & radiogalaxies

  31. Mout Lout tburstEburst,52 ~ ~ 0.005 Min For blazars: Ldisk=hMinc2 Mout ~ 0.01 G1Ldisk Min Outflowing/inflowing mass rate Lout=MoutGc2 ~0.1MO Min ~ MTorus/tburst GMTorusc2 G2MTorus,-1 h-1 Lout

  32. Jet vs disk power

  33. TeV BL Lacs

  34. High energy peak is getting large Mkn 421 Mkn 501 1959 1426 IR BGR Costamante et al. 2003

  35. Testing IR bkg models Dwek & Krennrich 2005

  36. d nc1/2 K-N: the same Whyd>20? nc/ns ~ g2 ns ns ~ g2Bd nc Bd ~ g-2 Lc/Ls ~ Ls/(B2d6) ~ Lsg4/d4 µ

  37. Subluminal motion for all TeV sources? Piner & Edwards, 2004

  38. G=15 G=4 Decelerating the entire jet ~1016cm Georganopoulos & Kazanas 2003 G’ IC is enhanced

  39. Georganopoulos & Kazanas 2003

  40. Instead, at the pc scale…. Mkn 501 Giroletti et al. 2004

  41. Cospatial fast spine & slow layer 1015 cm Ghisellini, Tavecchio, Chiaberge 2005 DRl~1016 cm DRs~1014 cm Strong feedback between spine and layer For both: enhanced IC emission

  42. B =1.3 G Le =4x1042 LB =1x1043Lp =2x1043 No feedback

  43. BL Lac Radiogalaxy

  44. FR1 BL Lac Spine-layer feedback UB~Urad 0735+178 B=5 G LB~Le~6x1044 Lp~7x1045 NGC 6251 B=1.8 G LB=4x1041 Le=2x1042 Lp=2x1043

  45. Fossati et al. 1998

  46. Having increased the B-field, we need fewer electrons to do the radiation we see The jet is lighter It is easier to make it decelerate

  47. Synchro and SSC K In K there is a loss of momentum… K’ And in K’? no, but the mass <g>me decreases. Gbulk remains the same

  48. External Compton: the rocket K more collimated than before (Dermer 1995) K’ Anisotropic! Loss of momentum recoil Important when <g>me~mp Gbulk decreases

  49. The Mkn 421 case

  50. Consequences • Low power jets decelerate more? • Extended emission smaller for TeV BL Lacs? • Large angles? Layer. Also GeV-TeV for radio-galaxies (GLAST)

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