Impulsive heating in coronal loops

Abstract

Observations of the solar-chromosphere transition region plasma show evidence of frequent microscale events, which have been proposed to be responsible for the heating of the solar atmosphere. One heating theory indicates that these small-scale events are driven by localized magnetic field reconnection. In this paper, we present the results of numerical calculations that describe the response of the coronal plasma to microscale heating pulses in a magnetic loop. In particular, we study the effects of energy input pulses injected randomly near the two footpoints of a semi-circular loop. We find that successive random pulses can maintain the plasma temperature on average at typical coronal values. Due to the randomness of the pulse injections, the resulting temperature profiles show temporal thermal bumps that could be connected to intermittent behavior in the transition region and the low corona of the quiet Sun.