Unformatted text preview: only pressure supported. Integrate the pressuresupport equation along z at r s to obtain P ( z )P (0) ’ G M ρ r 3 s Z z ds s exp ±s z c ² ’ P (0) ’ G M ρ z 2 c r 3 s for z c ¿ z ¿ r s which is the midplane pressure. There is little radial density structure, so ∂P ∂r . ∂P ∂z but ∂V ∂z ¿ ∂V ∂r so the pressure term in the radial stability equation must be very much smaller than the other two terms and may be neglected. Then the equation is trivial and yields M ’ r s v 2 φ G ’ 1 . 2 · 10 44 g ’ 6 · 10 10 M ¯ b) T = m p P (0) ρ k ’ G M m p z 2 c k r 3 s ’ v 2 φ m p z 2 c k r 2 s ’ 10 7 K c) Support arises from turbulent motion with < v z > of a few km/s....
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 Fall '08
 RABE
 Physics, Radiation, Trigraph, rs

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