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(Massive) Black Hole X-Ray Binaries
Roger BlandfordKIPAC, Stanford
+Jane Dai, Steven Fuerst, Peter Eggleton
(Also Hameury, J-P L)
RE J1034+396•z=0.042 Seyfert galaxy
•Lbol ~ 1044.7 erg s-1
•FUV-SX
•XMM-Newton observations•1 hr QPO in ~1 d observing•Best example to date in AGN of a phenomenon quite common in stellar XRB•<Q> ~ 16 overall but much higher for section of data •~7% sinusoidal profile•Interpreted as diskoseismic mode•Could it be an EMRI mass transfer binary?•Planetars???
2 xi 2010 KIAA 2
Conservative Mass transfer
Transfer m -> M at constant m+M, J J ~ mMP1/3
If M>>m and gravitational radiation wins,• dJ/dt~-m2M4/3P-7/3
If m fills Roche lobe, P~-1/2 ~m0.8 =>J~m1.3
• J decreases• Orbit expands• Period lengthens
2 xi 2010 KIAA
Stable Mass Transfer
3
cf Hameury et al
Relativistic Roche Problem
Riemann -> local tidal tensor. Evaluate volume within critical
equipotential and evaluate• r(L1)=0.3m1/3 P2/3 Ro
• (Roche)=90P-2 g cm-3
• Good for N, ISCO (all a)• Accurate interpolation
Lose mass through L1, L22 xi 2010 KIAA
Roche Potential
L1 L2
4
Pre-Roche evolution Gravitational radiation dominates
• Need PPN corrections to torque
Low mass star fills Roche lobe when P=PR=8m0.8hr
[ => m < 0.1 Mo ]
Outside ISCO• P > PISCO ~ M
[=>M<3x107Mo]
Time to overflow tR-t=2x105M6
-2/3m1.3[(P/PR)8/3-1] yr
2 xi 2010 KIAA 5
Stellar Evolution Differs from close binary
case tdynamical << ttransfer << tKelvin S[m] will be frozen Solve:
dP/dm=-Gm/4r4
dr/dm=1/4r2[S(m),P]
=> d log </d log m = =2 for convective low mass star
2 xi 2010 KIAA
dS/dm >=0
6
Period vs mass
2 xi 2010 KIAA 7
Post-Roche Evolution After mass transfer orbit expands
• P ~ m-/2
~ m-1 for low mass star
t-tR=1400M6-2/3m-1 P8/3 [(P/PR)11/3-1] yr; [~ 5000yr]
Conservative Mass loss dm/dt = (dm/dt)R = -1.3x1020M0.7P-0.3 g s-1 [~ 1021g s-1]
~ -m8.3 eventually till ttransfer > tKelvin
Dynamical complications• Holding pattern?• Interactions, drag
KIAA2 xi 2010 8
Mass transfer Mass flows from L1 onto
relativistic disk forming hotspot
Gas spirals in to rms before plunging into hole
Inclined orbits are more complex as streams may not self-intersect
Disk flow may have complex gaps and resonances
Hot spot Doppler beams emission
Also spiral shocks, eccentricity
2 xi 2010 KIAA
€
L[Ω*,r(L1)] = LK [rout ]
9
Observed X-ray emission
2 xi 2010 KIAA
a=0 a=0.998i=5
i=30 i=45a=0 a=0.998
i=30
10