... stars

Appendices A and B are only available in electronic form at http://www.edpsciences.org

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... almost

DM94 exclude convection at Rosseland mean optical depths $\tau<2/3$ implicitly by the specific $T(\tau)$ relation they use in their photospheric model, see Chabrier & Baraffe (1997) for a more detailed discussion.

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...1987)

The model described by Kuhfuß (1986) is very similar to the 1987 version but the latter contains a more careful discussion and treatment of the mixing-length limit of the model.

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... isopleths

From the greek words $\tau\hspace{-1pt}\grave{o}$ $\pi\hspace{-1pt}\lambda\tilde{\eta}\vartheta\hspace{-1pt}o\varsigma$ and $\stackrel{\textrm\small ,}{\iota}$ $\sigma\hspace{-1pt}o\pi\hspace{-1pt}\lambda\eta\vartheta\acute{\eta}\varsigma$ meaning "mass'' or "crowd'' and "being of the same mass'', respectively.

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... 1995)

The advantages of using higher order advection schemes in adaptive mesh radiation hydrodynamics have been demonstrated by Winkler & Norman (1986). "Radiative'' protostellar collapse has been calculated earlier by using second order advection methods in the WH80s code. Those calculations did use a different grid equation (Winkler & Norman 1986). The VIP code is the first radiation hydrodynamics code that combines more accurate advection schemes with the much clearer grid equation by Dorfi & Drury (1987). The VIP code is in many aspects related to the titan code (Gehmeyr & Mihalas 1993), that is the offspring of the Winkler WH80s code (see Mihalas 1998). All those codes are based on implicit numerical methods using a self-adaptive grid.

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... magnitude

We can estimate the mean mass accretion rate for star formation from such a cloud by $\dot{M}_{\rm Jeans} = M_{\rm Jeans} / \tau_{\rm dyn, Jeans}$, with $\tau_{\rm dyn, Jeans} = \lambda_{\rm Jeans} / c_{\rm T}$ and obtain $\dot{M}_{\rm Jeans} = 4 \pi^2/3 c_{\rm T}^3/G \sim c_{\rm T}^3/G$, which is a valid estimate as long as the mean cloud densities are close to those of equilibrium configurations (singular or regular) and the temperature, and as a consequence the sound speed, $c_{\rm T}$, does not change. For our cloud assumptions we obtain $\dot{M}_{\rm Jeans} = 2.3\times 10^{-5}~{M_\odot/\rm yr}$.

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... 1991a)

The optical depth scale height is equal to the pressure scale height in classical, compact static photospheres (Baschek et al. 1991), hence the $\tau$ refinement translates into a $H_{\rm p}$-refinement.

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