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 “blazar sequence” BL Lacs LBL and HBL
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. gpeak is the energy of electrons emitting at the peak of the SED
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 jetsG
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. Powerful jets are not magnetically dominated
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. Disk accretion rate (Eddington units)
Jet power vs disk Lum.
GRBs
BL Lacs, FSRQ, mQSO
Photon trapping
Ldisk Pjet
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 Rdiss proportional to MBH
RBLR proportional to (Ldisk)  UBLR=cost
For Ldisk/LEdd < Lc  no BLR (BL Lacs)
1/2

19. Ledlow & Owen
Ghisellini & Celotti 2001

20. The key ideas 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
1/2

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

22. The key ideas 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
1/2

23. The key ideas The key ansatz
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
1/2
The key ansatz
Pjet always 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

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

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

33. 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)

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

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

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

38. TeV BL Lacs

39. Subluminal motion for all TeV sources?
Mkn 421
bapp~ 0.03 – 0.1 (+-0.06) H
bapp~ 2.09 (+-0.53)
Mkn 501
bapp~ 0.05 – 0.54 (+-0.15)
bapp~ 0
bapp~ 0.93 (+-0.31)
bapp~ 0 – 1.15 (+-0.5)
Piner, Pant & Edwards 2008

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

41. 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

42. BL Lac
Radiogalaxy

43. spine layer Ghisellini Tavecchio Chiaberge 2005
Tavecchio Ghisellini 2008

44. Power of jets

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

46. G=10-20 Dissipation here? Yes! Dissipation here? NO! ~1017 cm
RBLR~1018 cm
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

47. Energy transport in inner jet must be dissipationless
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

49. Ravasio et al. 2000

50. Fossati et al. 1998

51. Gamma-ray blazars EGRET: ~60 blazars
Cherenkov: 21 blazars (+1 Radiogal)
GLAST
The Universe becomes opaque at z~0.1 at 1TeV at z~2 at 20 GeV
HESS+ MAGIC

52. The VHE extragalactic gamma-ray sky
20 BL Lacertae (18 HBL + 2 LBL))
1 radiogalaxy (M87, 16 Mpc)
1 FSRQs (3C279, z=0.536)
Name
Redshift
Mkn
Mkn
1ES
Mkn
1ES
PKS
BL Lacertae
PKS
RGB
ON231 (W Comae)
PKS H
1ES
1ES H
1ES
1ES
1ES
1ES PG

56. Extragalactic jets: a new perspective
G. Ghisellini in collaboration with F. Tavecchio
INAF – Osservatorio Astronomico di Brera
The blazar sequence
Power and content of jets
A new perspective

57. tcool 1/(gpeak U) = R/c 2
g gpeakU = const