The equation of line transfer in the comoving frame
with absorption and emission due to dust and gas
(see Peraiah & Wehrse 1978; Peraiah 1984; Wehrse & Kalkofen 1985) is
given by,

+ | ||

+ | ||

+ | (1) |

and

(2) |

where all the symbols have their respective usual meanings (See Paper I). Further, is the absorption coefficient of the dust and the dust source function is given by,

= | ||

+ | (3) |

where is the Planck function for the dust emission, the albedo of the dust and

We have adopted the "CELL" method described by Peraiah (1984) to solve the Eqs. (1)and (2); This is done by suitable discretization in frequency, angle as well as radius. The details of the method was given in Peraiah et al. (1987).

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