An approximate analytic solution to the coupled problems of coronal heating and solar-wind acceleration

Between the base of solar corona and Alfven critical point, solar-wind density decreases by approximately five orders magnitude, but temperature varies a factor only few. In this paper, I show that such quasi-isothermal evolution out to point is generic property outflows powered reflection-driven Alfven-wave (AW) turbulence, in which outward-propagating AWs partially reflect, counter-propagating interact produce cascade fluctuation energy small scales, leads turbulent heating. Approximating sub-Alfvenic region as isothermal, first present simplified calculation mass outflow rate, asymptotic wind speed, coronal neglects conductive losses wave pressure force. then develop more detailed model transition region, corona, accounts for heat flux from into momentum deposition AWs. solve analytically balancing, within heating against internal-energy radiation, pdV work, advection. The at determined locally balancing radiative cooling. equations two different parameter regimes. Analytic numerical solutions agree with number observations.