[Mesa-users] Ritter mass transfer equation

[Brian Jackson]

It looks like you are using an old version of MESA that has a typo.
Instead of $2 \pi/e$, that first term should be $2 \pi/\sqrt{e}$, and
that's what I see in the binary_mdot.f file for the latest version of
MESA that I have, 10108. Ritter's original paper also has the square
root, so it looks like the equation was mis-translated into MESA at
some point.

Brian Jackson
On Wed, Aug 15, 2018 at 3:27 AM 熊赫然 <xiongheran at ynao.ac.cn> wrote:
>
> Hello, everyone:
>
> Nowadays, i am trying to evolve binary system, but when i checked the mdot_scheme, i found something that confused me.
>
>
> When i checked binary_mdot.f, i found the mdot when i set mdot_scheme = 'Ritter' is given by b% mdot_thin0 = (2.0D0*pi/exp_cr(1.0d0)) * v_th*v_th*v_th * rl3/(b% s_donor% cgrav(1)*b% m(b% d_i)) * rho * F1 and v_th = sqrt(3.0 * kerg * b% s_donor% T(1) / (mp * b% s_donor% mu(1))) , i think it means eq1 (picture in attachment) , but when i read Ritter's paper, i think the mdot that Ritter gave should be eq2 (picture in attachment). I don't understand why the two equations are different or do i make some mistake?
>
>
> Can everyone help me?
>
>
> Sincerely,
>
> Heran, XIONG
>
>
>
>
> --
> Heran XIONG
> Yunnan Observatories, Academia Sinica
> Phoenix Mountain, East Suburb
> Kunming, 650011
> P.R. China
>
> Tel. +86-0871-67381984 (Office)
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