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Astrophysical Jets

Astrophysical Jets. Mario Livio Space Telescope Science Institute. Which Systems Have Highly Collimated Jets ?. Stellar. Extragalactic. Disks around Young Stars STScI-PRC99-05b. M87: AGN from 200,000 light years to 0.2 light year. Superluminal Motion in M87 HST-1.

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Astrophysical Jets

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  1. Astrophysical Jets Mario LivioSpace Telescope Science Institute

  2. Which Systems Have Highly Collimated Jets? Stellar Extragalactic

  3. Disks around Young Stars STScI-PRC99-05b

  4. M87: AGN from 200,000 light years to 0.2 light year

  5. Superluminal Motion in M87 HST-1 • Do FR I radio galaxies have relativistic jets like BL Lacs?

  6. “Superluminal” sources • GRS 1915+105V ~ 0.9c • Extragalactic jets showV > 0.995c

  7. Gamma Ray Bursts Fruchter et al. 2006

  8. Symbiotics Southern Crab NebulaHe2-104 STScI-PRC99-32

  9. Planetary Nebulae STScI-PRC97-38b

  10. Point-Symmetric Planetary Nebulae • IC 4634

  11. Point-Symmetric Planetary Nebulae

  12. Point-Symmetric Planetary Nebulae

  13. SS 433 Vermeulen et al. 1993

  14. Supersoft X-Ray Source RXJ 0513-69 Southwell et al. 1996

  15. Recurrent Novae and Symbiotics U Sco (1999) Hillwig, Livio & Honeycutt 2004 Lépine, Shara, Livio & Zurek 1999

  16. Pulsar Jets Vela Pulsar Crab Pulsar Chandra Chandra

  17. Do Jets Require an Accretion Disk? • What are the absolutely necessary ingredients for the mechanism of jet acceleration and collimation?

  18. [OI] l6300 Profiles for T Tauri Stars Redshifted component not seen because of disk. Edwards et al. 1987 Livio & Xu 1997

  19. X-Ray Spectroscopy of Accretion Disks • MCG-6-30-15 (Tanaka et al.) • Gravitational redshift plus Doppler shift • Evidence that  ~ max = 1/2 m

  20. Do Jets Require an Accretion Disk? Yes “Interacting winds”, “ion torus”, Pulsars, need more work

  21. Do Accretion Disks Require Jets or Outflows? • Are outflows/jets the main mechanism for transport/removal of angular momentum (Königl; Pudritz & Norman ’86; Li ’96)? • Angular momentum carried by wind

  22. Do Accretion Disks Require Jets or Outflows? Angular momentum that needs to be removed from disk For rA ~ 10r, only 1% of the accreted mass needs to be lost in wind.

  23. Behavior of Disk Radius During Dwarf Nova Outburst • At outburst, matter diffuses inward. Angular momentum of that matter is transferred to outer parts of the disk. • Radius expands • Observations • OY Car, HT Cas, Z Cha (Harrop-Allin & Warner ’96) • Disks in OY Car, HT Cas and Z Cha larger in outburst. U Gem Smak 1984

  24. Behavior of Disk Radius During Dwarf Nova Outburst Theory, disk instability Ichikawa & Osaki 1992; Livio & Verbunt 1988

  25. Do accretion disks require jets or outflows for angular momentum removal? I don’t think so. • Observations of rotation in jets and bipolar outflows are badly needed (velocity gradients).

  26. Other Clues on Jets Jet Origin

  27. Jets originate from the center of the accretion disk! • Models which work at all radii are probably not the “correct” ones, (e.g. self similar).

  28. Black Hole Jets • Two states: • dissipation and disk luminosity, • bulk flow and jet. Livio, Pringle, King 2003, 2004; Mirabel 1993, 1998; Fender 2003; Fabian 2002, 2003

  29. New Timescale Timescale for jettj ~ td2R/H 1/f power spectrum below a break frequency.King, Pringle, West, Livio 2004Hujeirat, Livio, Camenzind, Burkert 2003

  30. Which ingredients play a major role in the acceleration and collimation?

  31. Ingredients which may notbe absolutely necessary

  32. What Does Work? A reasonably ordered large-scale magnetic field threading the disk!

  33. Magneto-Centrifugal Jet Acceleration and Collimation • Acceleration like a bead on a wire up to the Alfven surface. • Acceleration optimal around inclination of 60°(Blandford & Payne 1982; Meier et al. 1997).

  34. Collimation Outside Alfven Surface Collimation by hoop stress? BUT Kink Instability Heyvaerts & Norman 1996

  35. Poloidal Collimation Necessary Conditions • Rdisk/Robject = Significant number of decades • Bz largest at inner disk but largest at outer disk e.g. Bz ~ (r/Rin)-1 Good collimation obtained forRAlfven ~ Rdisk Konigl & Kaatje 1994; Spruit 1996 Consequences Minimum opening angle of jetmin ~ (Rin/Rout)1/2

  36. M87 Junor, Biretta, Livio 1999

  37. Relativistic Outflow Magnetic flux tubes across horizon propel relativistic outflow.No collimationKoide 2004

  38. Are There Additional Ingredients? • Why are there radio-loud and radio-quiet AGN? • Why do CVs appear not to produce jets while PNe nuclei and SSS do? • How can pulsars produce jets?

  39. Conjecture • The production of powerful jets requires an additional heat/wind source. • Solutions to transsonic flow in disk corona (Ogilvie & Livio 1997, 2000)  for strong B a potential difference exists even for i > 30 (Df ~ B4).

  40. Energy Extraction from Spinning Holes • Penrose Process • Negative energy orbits within “ergosphere”. • Need fortuitous collision or deus ex machina. • Electromagnetic Extraction • Magnetic fields supported by external current interacts with “conducting” horizon. • Energy extracted to jet and disk. • Corotating observer sees energy flow across horizon. • Conserved outward flow of energy, angular momentum in non-rotating frame. • Reduce m; increase m0.

  41. Radio Loud vs. Radio Quiet AGN Sikora et al. 2006 Xu, Baum & Livio 1999 Rawlings 1994 Central engineparameters:

  42. Spins of Black Holes? • RISCO, a*, determined on the basis of x-ray data. • Study of plunging orbits important. McClintock et al. 2006 Shafee et al. 2006 Zhang, Cui & Chen 1997

  43. Critical Observations For the General Picture • Reliable determinations of • Determinations of the collimation scale in all classes of objects. • Long-term monitoring for variablity patterns in double-peaked emission lines in AGN. Power spectra. • Detection and measurement of rotation and of toroidal magnetic fields in jets and bipolar outflows. • More evidence for precession. • Breaks in afterglows of GRBs.

  44. Critical Observations For the Conjecture • Searches for jets in other SSS, in PNe, in other XRTs (during flares, e.g. A0620-00, GS2023+338, GS 1124-683, Cen X-4, AQL X-1), and other symbiotic systems, in CVs! • Determination of black hole masses in AGN. • Determination of black hole spins in AGN (e.g., through Fe Ka line profiles). • Determination of black hole spins in stellar mass black holes. • Determine whether pulsars can generate highly collimated jets.

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