adios revisited mitch begelman jila, university of colorado adios revis it ed

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

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ADIOS Revisited

Mitch Begelman

JILA, University of Colorado

ADIOS Revis it ed

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

HOPEFULLY LESS WRONGStarted: 1998 AAS, San Diego

The ADIOS model addresses a fundamental problem in accretion theory…

HOW DOES ROTATING GAS ACCRETE IF IT CAN’T RADIATE

EFFICIENTLY?

ACCRETION REQUIRES TORQUE +

TORQUE TRANSPORTS ENERGY

G

Angular Momentum Flux:

Energy Flux:

outward~Torque MG

outwardG

THE PROBLEM:

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

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

• 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

THE ADIOS MODEL

Mass Outflow or circulation

Energy 1 R

Ang.Mom. 2/1R

10 n

RM n0BInflow

0B

Mass

Energy

Ang. Mom.

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

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

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

Hawley & Balbus 02

SIMULATIONS SHOW MORE RESTRICTIVE BEHAVIOR...

1~n

Lindner, Milosavljevic, Couch, and Kumar 2009, preprint

RM

inM

outMoutinnet MMM

Lindner, Milosavljevic, Couch, and Kumar 2009, preprint

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.

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

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

BREEZE MODELS

Bound, viscous inflow

Unbound, very slow outflow

Viscous stress important in outflow

WIND MODELS

Bound, viscous inflow

Unbound, dynamical outflow

Viscous stress unimportant in outflow

local) transfer mom. ang. (if

:PREDICTION

inout LL3

2~

WIND MODELS

OUTFLOW CAN BE SUBSONIC OR SUPERSONIC …

BUT REQUIRES HIGH ENERGY INPUT ()

SUBSONIC

SU

PE

RS

ON

IC

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 …

Started: 1987 AAS, Pasadena

Gestation period: 4 months

Started: 1998 AAS, San Diego

Gestation period: 7 months

Started: 1998 Texas Symposium, Paris

Gestation period: 5 years

Started: 1999 KITP BH Meeting, Santa Barbara

Gestation period: 8 years

Started: 2009 BlandfordFest, Stanford

Gestation period: ??ar

Xiv

:??1

0.23

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