adios revisited

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ADIOS Revisited Mitch Begelman JILA, University of Colorado ADIOS Revis it ed

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ADIOS Revisited. ed. ADIOS Revis. it. Mitch Begelman JILA, University of Colorado. Started: 1987 AAS, Pasadena. ROGER’S WRONGEST PAPER?. Started: 1998 AAS, San Diego. HOPEFULLY LESS WRONG. The ADIOS model addresses a fundamental problem in accretion theory…. - PowerPoint PPT Presentation

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Page 1: ADIOS Revisited

ADIOS Revisited

Mitch Begelman

JILA, University of Colorado

ADIOS Revis it ed

Page 2: ADIOS Revisited

ROGER’S WRONGEST PAPER?Started: 1987 AAS, Pasadena

Page 3: ADIOS Revisited

HOPEFULLY LESS WRONGStarted: 1998 AAS, San Diego

Page 4: ADIOS Revisited

The ADIOS model addresses a fundamental problem in accretion theory…

HOW DOES ROTATING GAS ACCRETE IF IT CAN’T RADIATE

EFFICIENTLY?

Page 5: ADIOS Revisited

ACCRETION REQUIRES TORQUE +

TORQUE TRANSPORTS ENERGY

G

Angular Momentum Flux:

Energy Flux:

outward~Torque MG

outwardG

THE PROBLEM:

Page 6: ADIOS Revisited

IN A THIN ACCRETION DISK:

G

Local rate of energy release:

Local rate of dissipation:

R

GMM

2

R

GMM

23

2/3 of energy dissipated at R transported from <R by viscous

torque

Page 7: ADIOS Revisited

IN A RADIATIVELY INEFFICIENT ACCRETION FLOW:

G

Energy transport from small R by torque unbinds gas at large R

Energy Transport:

Bernoulli Function

02

v B

B~2

h

MG

Page 8: ADIOS Revisited

• 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-OUTFLOWSOLUTION (Blandford & Begelman 99)

1 g of gas accreting at r ~ m

can liberate 1 kg of gas at r ~ 1000 m

Page 9: ADIOS Revisited

THE ADIOS MODEL

Mass Outflow or circulation

Energy 1 R

Ang.Mom. 2/1R

10 n

RM n0BInflow

0B

Mass

Energy

Ang. Mom.

Page 10: ADIOS Revisited

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

Page 11: ADIOS Revisited

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

Page 12: ADIOS Revisited

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

Page 13: ADIOS Revisited

Hawley & Balbus 02

SIMULATIONS SHOW MORE RESTRICTIVE BEHAVIOR...

1~n

Page 14: ADIOS Revisited

Lindner, Milosavljevic, Couch, and Kumar 2009, preprint

RM

inM

outMoutinnet MMM

Page 15: ADIOS Revisited

Lindner, Milosavljevic, Couch, and Kumar 2009, preprint

Page 16: ADIOS Revisited

TWO-ZONE ADIOS MODEL

Mass Outflow

Energy 1 R

Ang.Mom. 2/1R

10 n

RM n0BInflow

0B

Exchange: Mass

Energy

Ang. Mom.

AVERAGE OVER STREAMLINES

CONSERVE ENERGY, ANG. MOM. IN EACH ZONE

CONSERVE EXCHANGED ENERGY, ANG. MOM.

Page 17: ADIOS Revisited

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 1 R

Ang.Mom. 2/1R0BInflow

0B

1

~

n

RM

Exchange: Mass

Energy

Ang. Mom.

CENTRAL

ACCRETION ENERGY

DRIVES OUTFLOW

1R

M

Page 18: ADIOS Revisited

BREEZE MODELS

Bound, viscous inflow

Unbound, very slow outflow

Viscous stress important in outflow

Thin disk limit, a=0

Marginally bound inflowStress vanishes in outflow

No slow solution possible

Page 19: ADIOS Revisited

BREEZE MODELS

Bound, viscous inflow

Unbound, very slow outflow

Viscous stress important in outflow

Page 20: ADIOS Revisited

WIND MODELS

Bound, viscous inflow

Unbound, dynamical outflow

Viscous stress unimportant in outflow

local) transfer mom. ang. (if

:PREDICTION

inout LL3

2~

Page 21: ADIOS Revisited

WIND MODELS

OUTFLOW CAN BE SUBSONIC OR SUPERSONIC …

BUT REQUIRES HIGH ENERGY INPUT ()

SUBSONIC

SU

PE

RS

ON

IC

Page 22: ADIOS Revisited

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

– Total energy supply |Eaccacc|Ṁacc~Ṁ/R

– Fraction to outflow, 1- carried outward by inflowing gas

– Details of inner accretion flow determine , • Applications: SS433, Galactic Center …

Page 23: ADIOS Revisited

Started: 1987 AAS, Pasadena

Gestation period: 4 months

Page 24: ADIOS Revisited

Started: 1998 AAS, San Diego

Gestation period: 7 months

Page 25: ADIOS Revisited

Started: 1998 Texas Symposium, Paris

Gestation period: 5 years

Page 26: ADIOS Revisited

Started: 1999 KITP BH Meeting, Santa Barbara

Gestation period: 8 years

Page 27: ADIOS Revisited

Started: 2009 BlandfordFest, Stanford

Gestation period: ??ar

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