Articulo
Analytical solutions for radiation-driven winds in massive stars II : The δ-slow regime
Registro en:
issn:0035-8711
issn:1365-2966
Autor
Araya, I.
Christen, A.
Curé, Michel
Cidale, Lydia Sonia
Venero, Roberto Oscar José
Arcos, C.
Gormaz Matamala, A. C.
Haucke, Maximiliano
Escarate, P.
Clavería, H.
Institución
Resumen
Accurate mass-loss rates and terminal velocities from massive stars winds are essential to obtain synthetic spectra from radiative transfer calculations and to determine the evolutionary path of massive stars. From a theoretical point of view, analytical expressions for the wind parameters and velocity profile would have many advantages over numerical calculations that solve the complex non-linear set of hydrodynamic equations. In a previous work, we obtained an analytical description for the fast wind regime. Now, we propose an approximate expression for the line-force in terms of new parameters and obtain a velocity profile closed-form solution (in terms of the Lambert W function) for the δ-slow regime. Using this analytical velocity profile, we were able to obtain the mass-loss rates based on the m-CAK theory. Moreover, we established a relation between this new set of line-force parameters with the known stellar and m-CAK line-force parameters. To this purpose, we calculated a grid of numerical hydrodynamical models and performed a multivariate multiple regression. The numerical and our descriptions lead to good agreement between their values. Facultad de Ciencias Astronómicas y Geofísicas Instituto de Astrofísica de La Plata