Non-local heat transport in static solar coronal loops

Abstract

We investigate the limits of applicability of the Spitzer-Harm thermal conductivity in solar coronal loops and show that the ratio λ0/LTof electron mean-free path to temperature scale height in large-scale structures can approach the limits of the Spitzer-Harm theory. We use a non-local formulation of heat transport to compute a grid of loop models: the effects of non-local transport on the distribution of differential emission measure are particularly important in the coronal part of loops longer than the pressure scale height sp.We derive a scaling law for λ0/LTin the corona, showing that it grows exponentially with L/sp, and discuss effects of non-local heat transport in the transition region.