Abstract:
A computationally simple method for solving the line transfer in comoving frame has been described for radially expanding spherical medium. We have assumed a radially increasing velocity distribution and a non-LTE (where V (r) is the velocity at the radial point r in men thermal units, Cos-1 μ is the angle made by the ray with specific intensity I (r, μ, v) of frequency v, with the radius vector at r) will reduce to a single tridiogonal matrix. The boundary conditions for the frequency derivative can be introduced through the elements of the first and the last rows. The method is quite stable for any velocity law and any type of inhomogeneous media. We have considered into the observers line of sight have been presented.