Abstract
Cool giant and supergiant stars generally present low velocity winds with high mass-loss rates. Several models have been proposed to explain the acceleration process of these winds. Although dust is known to be present in these objects, the radiation pressure on these particles is uneffective in reproducing the observed physical parameters of the wind. The most promising acceleration mechanism cited in the literature is the transference of momentum and energy from Alfvén waves to the gas. Usually, these models consider the wind to be isothermal. We present a stellar wind model in which the Alfvén waves are used as the main acceleration mechanism, and determine the temperature profile by solving the energy equation taking into account both the radiative losses and the wave heating. We also determine, self-consistently, the magnetic field geometry as the result of the competition between the magnetic field and the thermal pressure gradient. As the main result, we show that the magnetic geometry presents a super-radial index in the region where the gas pressure is increasing. However, this super-radial index is greater than that observed for the solar corona.
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Airapetian, V.S., Carpenter, K., and Ofman, L.: 2003, AAS 202, 3214.
Bravo, S., and Stewart, G.A.: 1997, AdSpR 20, 35.
Dobrzycka, D., Cranmer, S.R., Panasyuk, A.V., Strachan, L., and Kohl, J. L.: 1999, JGR 104, 9791.
Dupree, A.K.: 1986, ARA & A 24, 377.
Guandalini, R., Busso, M., Ciprini, S., Silvestro, G., and Persi, P.: 2006, A & A 445, 1069.
Hartmann, L., and MacGregor, K.B.: 1980, ApJ 242, 260.
Hartmann, L., Edwards, S., and Avrett, E.: 1982, ApJ 261, 279.
Jatenco-Pereira, V., and Opher, R.: 1989, A & A 209, 327.
Lamers, H.J.G.L.M., and Cassinelli, J.P.: 1999, Introduction to Stellar Winds, Cambridge University Press, New York.
Lagage, P.O., and Cesarsky, C.J.: 1983, A & A 125, 249.
Longcope, D.W., and Klapper, I.: 1997, ApJ 488, 443.
Pneuman, G.W., Solanki, S.K., and Stenflo, J.O.: 1986, A & A 154, 231.
Sandin, C., and Hofner, S.: 2003, A & A 404, 789.
Schmutzler, T., and Tscharnuter, W.M.: 1993, A & A 273, 318.
Spruit, H.C.: 1981, A & A 98, 155.
Suzuki, T.K., and Inutsuka, S.: 2005, ApJL 632, 49.
Usmanov, A.V., Goldstein, M.L., Besser, B.P., and Fritzer, J.M.: 2000, JGR 105, 12675.
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Vidotto, A.A., Falceta-Gonçalves, D. & Jatenco-Pereira, V. A Self-Consistent Determination of the Temperature Profile and The Magnetic Field Geometry in Winds of Late-Type Stars. Space Sci Rev 122, 181–188 (2006). https://doi.org/10.1007/s11214-006-7286-z
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DOI: https://doi.org/10.1007/s11214-006-7286-z