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YSO Jets: Feedback from Mesoscopic to Macroscopic scales. Adam Frank University of Rochester Andrew Cunningham , Kris Yirak Eric Blackman, Alice Quillen, Sorin Mitran (UNC), John Bally (CU), Pat Hartigan (Rice). The Tool: AstroBEAR AMR Code. Cunningham, Frank, Varniere & Mitran 2007*.
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YSO Jets:Feedback from Mesoscopic to Macroscopic scales Adam Frank University of Rochester Andrew Cunningham, Kris Yirak Eric Blackman, Alice Quillen, Sorin Mitran (UNC), John Bally (CU), Pat Hartigan (Rice)
The Tool:AstroBEAR AMR Code Cunningham, Frank, Varniere & Mitran 2007* • “Block” AMR • Choice of solvers/integrators • Parallel – load balance • Multi-physics modules: • Ionization and H2Chemistry • heat conduction • *self-gravity • *rad trans (diff limit) • MHD Flux conservation via CT
Radiative Outflows in Heterogeneous MediaCunningham, Frank, Varniere & Mitran 2007*
Feedback on Meso & Maco Scales. • Microscopic = launch region (L < 100 AU) • Mesoscopic = Individual outflow (L < .1 pc) • Macroscopic = Cluster/pc-scale flow ( L ~ 1 pc) • Mesoscopic • Outflow’s affect on “envelope”: • density • velocity • emission
Scattered Light CavitiesLaski, Frank, Cunningham 2007* • Explore envelope shaping via: • Jets • Wide Angle Winds • Envelope: rotating collapse. • Use scattered-light code for images • Wood et al… • Shang et al. 2006 10000 au
Macroscopic Scales:Outflow Feedback & Turbulence • Can space-filling isotropic turbulence be driven by needles (jets), or balloons (outflows)? • Explicate mechanisms. • Connection with observational structures. • Global Analytics – Matzner, Tan, Krumhotz, others • Global sims – Maclow 2000, Nakamura & Li 2005, 2007 • Resolution critical for jet sims : Rj ~ 20 zones. • Observation: total outflow energy budgets = cloud/cluster turbulent energy (Walawender et al 2006, Sandell & Knee 2001). • Observation: Parsec outflows common (Bally, Devine Reipurth, Ray) • Typical cloud size/stellar density => whole cluster overrun by outflows. • Tens/Hundreds proto-stars eject enough Ek replenish Eturb.
Project 1:Outflow Collisions as a Route to TurbulenceExplore effect of single collisions on accelerating ambient material. Vary impact parameter b Cunningham, Frank & Blackman 2006
b = 0 b = rj b = 5.3 rj Results b=rj b=5rj b=0 Collisions reduce effective “entrainment” Increase Radiative Losses Bad for turbulence. b=0 b=rj b=5rj
Project 2:Fossil Cavities as Intermediaries to Protostellar TurbulenceObservations of NGC 1333 : Quillen et al 2005Simulations of Fossil CavitiesCunningham et al 2006
Project 2: NGC 1333: A Test Case(Quillen et al 2005) • NGC 1333: Numerous active outflows (Knee & Sandell 2000 Walsh et. al 2006) • Explore High Rez 13CO Data - No correlation of outflows with velocity dispersion. (Ridge et al, COMPLETE) • But…numerous low V cavities seen in channel maps. • No stellar source at center of cavities – Fossil Cavities of extinct outflows. • Scaling relation: Ek(fossil outflows) ~ Eturb
Cavity SimulationsCunningham, Frank, Blackman & Quillen 2006 • Explore time-decaying Jets/WAW outflow evolution (Bertout et al 96) • Outflow power decays after 104 y. • Simulation runs for 105 y • Run to 0.5 pc scales • Compare with scaling relations of Quillen et al. • Compare with PV diagrams
Fossil Cavity Sims: Jets and WAW Collimated Jet Wide Angle Wind (Matzner Class Sol) • Strong deceleration • Rarefactions backfill cavity
Fossil Cavity Sims: Results Quillen et al scaling relation for momentum Simulation comparison: deviation from scaling relation small WAW jets Time dependent jets/wind = fossil cavities = turbulent support
Project 3:Radiative Jets in Turbulent MediaMechanism for a single jetCunningham et al. 2007*
Time-dependent Jets in Turbulent Environment Long Period 2-D slices of 3-D simulation Short Period
Time Dependent Jets in a Turbulent Environment Intermediate pulse Long pulse • Without jet, turbulence decays as expected. • With jet, “turbulence” re-energized on all scales. • With jet long “driving” scales energized which • not previously present.
Future: Focus on Individual ObjectsL1551Frank, Bally, Blackman, Hartigan 200x
Conclusions • Colliding Jets • Interactions of active outflows not important. • NGC 1333/Fossil Cavities • Fossil cavities “store” momentum. • Fossil cavities = transient jets/outflows • Momentum budgets match • Outflows in Turbulent Media • Outflows re-energize turbulence. “Region” between Meso-scale and Macro-scale likely to matter.