adios revisited
DESCRIPTION
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 PresentationTRANSCRIPT
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
27v1
[as
tro-
ph.H
E]
17
Oct
20?
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