Analytical solutions for radiation-driven winds in massive stars II : The δ-slow regime

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 veloc...

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Detalles Bibliográficos
Autores principales: 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.
Formato: Articulo Preprint
Lenguaje:Inglés
Publicado: 2021
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/124521
Aporte de:SEDICI (UNLP) de Universidad Nacional de La Plata Ver origen
Descripción
Sumario: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.