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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 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)
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)
Clumps, Jets and Bubbles • Astrophysics • Complex hydro/MHD systems • Non-linear, time dependent behaviors • Tools • Analysis • Numerical Simulation • Direct laboratory experiments!
UR/LLE Omega Laser The New Laboratory Astrophysics Remington, Drake, Arnett, Kane, Klein et al • 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!
Lab Jet Experiments:Similarity Energy Equations are invariant under change of variables (scales)
… and at larger scales: • Mass outflows from AGN’s Application # 1 Clumpy Flows • I finally have something to say!!! • 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
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
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
Clumpy Flows: Characterizing the System Mixing Note: Do not see mass loading! Clumps disperse first (cooling? Mellema et al 2002)
Critical density, critical separation between clump centers normal to the flow: Clumpy Flows: Characterizing the System What Matters (build on Klein et al 2002)… • 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
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
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
Clumpy Flows (in the lab)Poludnenko et al 2002 • What you can see. • “OK” clump/ambient medium density ratio (40) • Reasonably steady shock • Strong enough shock convert clumps to plasma
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)
Application # 2 Astrophysical Jets • Unresolved issues: • Interaction and the generation of turbulence • (Cunningham et al 2002)
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
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
Test Canto Jet Formation Model Vz = 200 km/s M > 15 Vz = 200 km/s M > 15 Low Z = low radiative cooling = poor collimation
Future: Test Jet/ISM interactions • Opportunity to test • a variety of astrophysical • jet issues • Collimation • Propagation • Stability • MHD (?) • Pulsing (?)
Application # 3 PNe • PNe as FAST ROTATORS • Frank et al 2002 • Magneto-centrifugal Disk Wind Models for PNe (Peltier & Pudritz 1992) • Can fully account for “Momentum Excess” of Bujarrabal et al. (2001)
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 • PNe = winds from strongly magnetized rotators.
Radiative Cooling Jets! Vz = 200 km/s M > 15 Use W wires, high rate of cooling (proportional to Z)
“Supernova by Jet”Khokhlov et al • “Plug” of Mg creates collimated flow. • SN driven by jet from core
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
Experiments on the Gekko laser -> Shock-Cloud collisions Kang, et al.