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ADIOS Revisited Mitch Begelman JILA, University of Colorado ADIOS Revis it ed
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ROGER’S WRONGEST PAPER? Started: 1987 AAS, Pasadena
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HOPEFULLY LESS WRONG Started: 1998 AAS, San Diego
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The ADIOS model addresses a fundamental problem in accretion theory… HOW DOES ROTATING GAS ACCRETE IF IT CAN’T RADIATE EFFICIENTLY?
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ACCRETION REQUIRES TORQUE + TORQUE TRANSPORTS ENERGY G Angular Momentum Flux: Energy Flux: THE PROBLEM:
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IN A THIN ACCRETION DISK: G Local rate of energy release: Local rate of dissipation: 2/3 of energy dissipated at R transported from <R by viscous torque
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IN A RADIATIVELY INEFFICIENT ACCRETION FLOW: G Energy transport from small R by torque unbinds gas at large R Energy Transport: Bernoulli Function
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Torque a “conveyor belt” for liberated energy Flow must find a way to limit energy transported outward from smaller r –Mass loss or circulation –Small fraction of supplied mass reaches BH ADIOS = ADIABATIC INFLOW-OUTFLOW SOLUTION (Blandford & Begelman 99) 1 g of gas accreting at r ~ m can liberate 1 kg of gas at r ~ 1000 m
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THE ADIOS MODEL Mass Outflow or circulation Energy Ang.Mom. Mass Energy Ang. Mom.
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SELF-SIMILAR DISK WINDS Wind: Inviscid outflow with B < 0 Disk: Viscous flow with B < 0 Jet: Evacuated cone Entropy increases at disk- wind interface High shear across wind No internal mixing across streamlines Huge parameter space of solutions Blandford & Begelman 2004
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SELF-SIMILAR DISK WINDS Wind: Inviscid outflow with B < 0 Disk: Viscous flow with B < 0 Blandford & Begelman 2004 Entropy increases at disk- wind interface
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SELF-SIMILAR DISK WINDS Wind: Inviscid outflow with B < 0 Disk: Viscous flow with B < 0 Blandford & Begelman 2004 Entropy increases at disk- wind interface High shear across wind No internal mixing across streamlines Huge parameter space of solutions 0<n<1
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Hawley & Balbus 02 SIMULATIONS SHOW MORE RESTRICTIVE BEHAVIOR...
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Lindner, Milosavljevic, Couch, and Kumar 2009, preprint
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TWO-ZONE ADIOS MODEL Mass Outflow Energy Ang.Mom. Exchange: Mass Energy Ang. Mom. AVERAGE OVER STREAMLINES CONSERVE ENERGY, ANG. MOM. IN EACH ZONE CONSERVE EXCHANGED ENERGY, ANG. MOM.
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TWO-ZONE ADIOS MODEL NO SOLUTION UNLESS: INCLUDE CENTRAL ENERGY SOURCE n ≈ 1 TOTAL POWER AVAILABLE FRACTION DRIVES OUTFLOW, FLOWS THRU DISK Mass Outflow Energy Ang.Mom. Exchange: Mass Energy Ang. Mom. CENTRAL ACCRETION ENERGY DRIVES OUTFLOW
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BREEZE MODELS Bound, viscous inflow Unbound, very slow outflow Viscous stress important in outflow Thin disk limit, a=0 Marginally bound inflow Stress vanishes in outflow No slow solution possible
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BREEZE MODELS Bound, viscous inflow Unbound, very slow outflow Viscous stress important in outflow
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WIND MODELS Bound, viscous inflow Unbound, dynamical outflow Viscous stress unimportant in outflow
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WIND MODELS OUTFLOW CAN BE SUBSONIC OR SUPERSONIC … BUT REQUIRES HIGH ENERGY INPUT ( ) SUBSONIC SUPERSONIC
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CONCLUSIONS A new type of ADIOS solution –“well-mixed” outflow Explains Ṁ ~R scaling Inflow and outflow exchange M, L, but little E Energy to drive outflow comes from center acc –Total energy supply |E acc | Ṁ acc ~ Ṁ /R –Fraction to outflow, 1- carried outward by inflowing gas –Details of inner accretion flow determine , Applications: SS433, Galactic Center …
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Started: 1987 AAS, Pasadena Gestation period: 4 months
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Started: 1998 AAS, San Diego Gestation period: 7 months
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Started: 1998 Texas Symposium, Paris Gestation period: 5 years
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Started: 1999 KITP BH Meeting, Santa Barbara Gestation period: 8 years
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Started: 2009 BlandfordFest, Stanford Gestation period: ?? arXiv:??10.2327v1 [astro-ph.HE] 17 Oct 20??
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