  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 Alfven waves to the gas. Usually, these models consider the
wind to be isothermal. We present a stellar wind model in which the Alfven
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 pressures gradient. As main result, we show that the
magnetic geometry present 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.
