Hydrodynamic Models of Line-Driven Accretion Disk Winds III: Local Ionization Equilibrium
نویسندگان
چکیده
We present time-dependent numerical hydrodynamic models of line-driven accretion disk winds in cataclysmic variable systems and calculate wind mass-loss rates and terminal velocities. The models are 2.5-dimensional, include an energy balance condition with radiative heating and cooling processes, and includes local ionization equilibrium introducing time dependence and spatial dependence on the line radiation force parameters. The radiation field is assumed to originate in an optically thick accretion disk. Wind ion populations are calculated under the assumption that local ionization equilibrium is determined by photoionization and radiative recombination, similar to a photoionized nebula. We find a steady wind flowing from the accretion disk. Radiative heating tends to maintain the temperature in the higher density wind regions near the disk surface, rather than cooling adiabatically. For a disk luminosity Ldisk = L , white dwarf mass Mwd = 0.6M , and white dwarf radii Rwd = 0.01R , we obtain a wind mass-loss rate of Ṁwind = 4 × 10−12M yr−1, and a terminal velocity of ∼ 3000 km s−1. These results confirm the general velocity and density structures found in our earlier constant ionization equilibrium adiabatic CV wind models. Further we establish here 2.5D numerical models that can be extended to QSO/AGN winds where the local ionization equilibrium will play a crucial role in the overall dynamics. Subject headings: accretion, accretion disks — hydrodynamics — novae, cataclysmic variables — stars: mass-loss Universidad Maŕıtima del Caribe, Departamento de Ciencias Básicas, Catia la Mar, Venezuela
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