Solutions for the stellar winds of hot luminous stars are obtained by solving the magnetohydrodynamic (MHD) equations, combined with the theory of radiation-driven winds. The formalism is basically the same as developed by Rotstein & Giménez de Castro (1996). We have considered the interaction of radiation pressure with an open magnetic field . The magnetic field lines are pushed by the intense radiation field and adopt a purely radial configuration:
and the polar magnetic flux at the photosphere:
Rotstein & Giménez de Castro (1996) assume all the lines contributing to the radiation pressure are optically thick (α = 1) in order to decouple the MHD equations. Here the model has been improved to adopt a value of α = 0.6 which is a better approach for A-supergiants.