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YSO Jets: Feedback, Meso and Macro-scales. Adam Frank University of Rochester Andrew Cunningham(!) , Kris Yirak Eric Blackman, Alice Quillen,. Feedback and “Protostellar” Turbulence. Can space-filling isotropic turbulence be driven by sticking needles, (balloons) into molecular clouds?
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YSO Jets: Feedback, Meso and Macro-scales Adam Frank University of Rochester Andrew Cunningham(!), Kris Yirak Eric Blackman, Alice Quillen,
Feedback and “Protostellar” Turbulence. • Can space-filling isotropic turbulence be driven by sticking needles, (balloons) into molecular clouds? • How to multiple outflows interact with a heterogenious medium • Can we explicate mechanisms by which time-dependent jets give up energy/momentum to turbulent medium. • Can we find connection with observational strutures. • Can we connect the properties of the stars to the properties of the outflows • Observation: total outflow energy budgets = cloud turbulent energy • Observation: Parsec outflows common • Volume fill ratio • L=1 pc, Rbs=0.1 pc, N=32 pc-3 => • 32 protostars pc-3 = whole cloud or core overrun by outflows. • Tens/Hundreds proto-stars eject enough Ek replenish Eturb.
Feedback on Meso & Maco Scales. • Mesoscopic = the scale of individual outflow • (L < 1 pc) • Macroscopic = scale of the entire cluster ( L ~ 1 pc)
The Tool:AstroBEAR AMR Code • “Block” AMR – Retain grids upon refinement (Burger & Collella) • Set of Riemann solvers (Full, Roe, MHD). • Parallel – load balance and domain decomposition • Built-in physics modules: • Time-dependent Ionization and H2Chemistry • heat conduction (multi-grid) • *self-gravity • *rad trans (diff limit) • MHD Flux conservation via CT
Radiative Outflows in Heterogenious MediaCunningham, Frank, Varniere & Mitran 2007
Project 1:Outflow Collisions as a Route to TurbulenceExplore effect of single collisions on accelerating ambient material. (Jet)2, (Wide Angle Wind) 2.Vary impact parameter b Cunningham, Frank & Blackman 2006
Results b=rj b=5rj b=0 b=0 b=rj b=5rj
b = 0 b = rj b = 5.3 rj • RESULTS • For jets we find n ~ 1.7 • Little difference between interacting (b = 0, rj) and non-interacting cases (b >> rj)! • Surface Area Effect – 2 jets become 1 M vs V Plots • M(v) or dP/dv diagnostic for molecular outflows • Power law for low velocities. Collisions reduce effective “entrainment” Increase Radiative Losses Bad for turbulence. Jet WAJ
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 • Explore High Rez 13CO Data - No correlatation of outflows with velocity dispersion • But…numerous low V cavities seen in channel maps. • No stellar source at center of cavities – Fossil Cavities of extinct outflows. • In Fossil Cavities: Ek(outflow) ~ 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 2005 • 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 MediaThe mechanism for a single jetCunningham et al. 2006
Project 3: Jets in a Turbulent Environment 2-D slices of 3-D simulation
Conclusions • Colliding Jets • Interactions of active Jets may not matter • Look at time and space domain • NGC 1333/Fossil Cavities • Active jets do not couple well to cloud • Fossil cavities “store” momentum • Energy and Momentum budgets OK • Fossil cavities “well represented” by transient jets