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Clumps, Jets and Bubbles Adventures on the SKY, In a BOX (computer), And in the LAB

Clumps, Jets and Bubbles Adventures on the SKY, In a BOX (computer), And in the LAB. Adam Frank (UR, LLE) A. Poludnenko, T. Gardiner, A Cunningham E. Blackman (UR), S Lebedev (IC), P. Drake (UM). Clumps, Jets and Bubbles The Dyson Era. Stellar Mass Loss Systems

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Clumps, Jets and Bubbles Adventures on the SKY, In a BOX (computer), And in the LAB

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  1. Clumps, Jets and BubblesAdventures on the SKY,In a BOX (computer),And in the LAB Adam Frank (UR, LLE) A. Poludnenko, T. Gardiner, A Cunningham E. Blackman (UR), S Lebedev (IC), P. Drake (UM)

  2. Clumps, Jets and BubblesThe Dyson Era • Stellar Mass Loss Systems • YSOs, Planetary Nebula,WR Bubbles, LBV, SNe • Observations • Wind blown BUBBLES. • Collimation (JETS) and Pulsing. • Heterogeneous plasma systems (CLUMPY FLOWS)

  3. Clumps, Jets and Bubbles • Astrophysics • Complex hydro/MHD systems • Non-linear, time dependent behaviors • Tools • Analysis • Numerical Simulation • Direct laboratory experiments!

  4. UR/LLE Omega Laser The New Laboratory Astrophysics • Astronomy has been observational science. • Astro environments = extremes of known physics. • High Energy Density (HED) Devices = Fusion Lasers, etc Create macroscopic volumes of HED plasmas Hydro/MHD Equations have scale-invariant solutions. SIMILARITY!

  5. … and at larger scales: • Mass outflows from AGN’s Application # 1 Clumpy Flows • Flows in inhomogeneous (clumpy) media are common • May be affected by mass-loading processes • Mixing, turbulence, shock propagation • Planetary Nebulae (e.g. NGC 7293, NGC 2392) • Wolf-Rayet nebulae (e.g. RCW 58) • Supernova remnants (e.g. Cygnus Loop) • Regions of low-mass star formation (e.g. Trapezium cluster, HH regions) • Molecular clouds

  6. The Physics of Clumpy Flows (in a box) Poludnenko, Frank & Blackman 2002 AMRCLAW based adaptive mesh refinement Mach 10.0 shock wave interacting with a system of 3 identical clouds, density contrast 500.0, adiabatic regime, shown is logarithmic density

  7. The Physics of Clumpy Flows (in a box) Poludnenko, Frank & Blackman 2002 Mach 10.0 shock wave interacting with a system of 14 identical clouds, density contrast 500.0, adiabatic regime, shown is logarithmic density

  8. Clumpy Flows: Characterizing the System Kinetic Energy Mixing Note: Do not see mass loading! Clumps disperse first (cooling? Mellema et al 2002)

  9. Critical density, critical separation between clump centers normal to the flow: Clumpy Flows: Characterizing the System What Matters? • thickness of the clump system as opposed to the total clump mass • clump distribution in the system as opposed to the total number of clumps Quantitative characteristics of clumpy systems: • Clump destruction length LCD, distance traveled by a clump prior to its breakup These two parameters distinguish between interacting and noninteracting regimes of clump system evolution

  10. Application # 1 Clumpy Flows (in the lab)Poludnenko et al 2002 Clumpy Cloud experiment design for HEDLA • Realistic clump volume fraction • “OK” clump/ambient medium density ratio (40) • Reasonably steady shock • Strong enough shock convert clumps to plasma

  11. Strongly Interacting Regeme •  y = 10 m  10 % dcrit •  x = 5.32 m  6 % LCD Simulating the Experiment (Large N system) • Mach 10 steady shock • System of 200 clumps • Density contrast  = 40 • Clump radius 25 m • Domain size 3 x 4 mm

  12. Application # 2 Astrophysical Jets • Appear in an ever widening array of environments: • AGN • YSOs • PNe • Unresolved issues: • Collimation (MHD fast rotators) • Propagation (variability, knots, stability) • Connection to wider bubbles (Gardiner et al 2002)

  13. Application # 2 Astrophysical Jets • Unresolved issues: • Interaction and the generation of turbulence • (Cunningham et al 2002)

  14. The Issue of Converging Conical Flows. Canto et al 1988 Frank Balick Livio 1996 Application # 2 Astrophysical Jets (in the lab)Lebedev et al 2002

  15. Application # 2 Astrophysical Jets (in the lab)Lebedev et al 2001 Z-Pinch Laboratory Jets • 16 wire Z-pinch: • MAGPIE Imperial College • “Precursor” plasma flows off wires. • Canto-esque conical converging flow

  16. Test Canto Jet Formation Model Vz = 200 km/s M > 15 Vz = 200 km/s M > 15 Low Z = low radiative cooling = poor collimation

  17. Future: Test Jet/ISM interactions • Opportunity to test • a variety of astrophysical • jet issues • Collimation • Propagation • Stability • MHD (?) • Pulsing (?)

  18. Jet Deflection via Side-Wind Interactions

  19. Conclusions: Future Directions • Clumpy Flows • Strong Cooling (Mellema et al.) • Mass Loading (How much? How fast?) • Global Configurations (3-D models) • Jets • MHD and Wide Angle Winds • Jet interactions driving turbulence • Laboratory Astrophysics • The hard but exciting work has just begun. • “Spirited Invention” • Bubbles • Magnetized Wind Bubble Model incorrect initial conds. • PNe = winds from strongly magnetized rotators.

  20. The Promise of HEDLANew Tools = New Science? • Astronomy has been observational science • few experiments possible (chemistry/dust) • Astro environments = extremes of known physics. • What does HIGH ENERGY DENSITY really mean. • HEDLA promises direct “access” to these environments. • Historical Precedent: Astrophysical Journal born after introduction of Spectrograph. EarlySpectrograph

  21. Lab Jet Experiments:Similarity Energy Equations are invariant under change of variables (scales)

  22. “Supernova by Jet”Khokhlov et al • “Plug” of Mg creates collimated flow. • SN driven by jet from core

  23. Experiments on the Gekko laser -> Shock-Cloud collisions Kang, et al.

  24. Paris Observatory April 2001 AMRCLAW based adaptive mesh refinement: resolution cascade 3 levels of refinement, equivalent resolution 800x1600, shown is density logarithm

  25. 2D vs. 3D instability Spherical divergence 2D simulation of SN1987A Muller, Fryxell, and Arnett (1991) Multi-interface coupling Multi-mode instability Experiments at Omega are probing several mechanisms present in supernova explosions

  26. Radiative Cooling Jets! Vz = 200 km/s M > 15 Use W wires, high rate of cooling (proportional to Z)

  27. on the other hand . . . • average clump separation along the flow  y = 10 m  10 % dcrit • average clump separation along the flow  x = 5.32 m  6 % LCD Therefore . . . Designed system is a system of strongly interacting clumps with both global and local evolution strongly affected by clump merging prior to breakup For the clump system implemented in the target design: • critical cloud separation dcrit = 4.2 cloud radii = 105 m • clump destruction length LCD = 3.54 cloud radii = 88 m • clump velocity at breakup vc = 36.5% post-shock velocity  18 km/sec • clump breakup time tCD = 12 ns

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