Prominence Formation by Localized Heating

Abstract

We describe a model for the formation of the cool condensed material that comprises a coronal filament or prominence. Numerical calculations are presented which demonstrate that large condensations form in a coronal loop if the loop satisfies two key requirements: (1) the loop heating must be localized near the chromospheric footpoints, and (2) the loop must have a dipped geometry in order to support the prominence condensation against gravity. We calculate one-dimensional equilibrium solutions for the equations of force and energy balance assuming optically thin radiative losses and a parameterized form for the coronal heating. This physical situation is modeled as a boundary value problem, which we solve numerically using a B-spline collocation scheme. The relation of our solutions to the well-known loop scaling laws is discussed, and the implications of our model for active region and quiescent prominences are discussed.