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M = Mini exp(t/tacc )
7
tacc = (4.4 ⇥ 10 yr)
✓
ṁE
ṁ
◆
t = tacc ln(Mfin /Mini ) = 0.74 Gyr
✏ = 0.1
Ṁ & 2 ⇥ 10
!
1
M /yr
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分裂片
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中心星
降着円盤
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rrad
3
lP
=
16⇡acG mT 4
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3
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tmig ⇠ 4 ⇥ 10 yr
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•