Cute sequence of star formation stages
More detailed generic powerpoint from Seminar in Theoretical Astrophysics, "Greatest hits"
The radio picture from the SKA
Binary Star Formation
During star formation, gravitational collapse forms a proto-star.
The released gravitational energy at first goes into
dissociating H2 and ionizing H and He.
Assume collapse from ∞ to the protostar radius, Rp:
α GM 2/Rp ≈
(M/mH)(XχH2 /2 +
XχH + YχHe /4),
where α is a number of order unity depending on radiative losses.
Remember that for polytropes Ω = −[3/(5 − n)] GM 2/R, and for an ideal gas n = 1.5.
Rp/Rs ≈ 50 (M/Ms) /(1 − 0.2X )
Te ≈ 2600 μ13/51 (M/Ms)7/51 (L/Ls)1/102 K.
L ∝ M 22/5Te4/5.