A model for intermediate temperature solar coronal loops

Simple hydrostatic equilibrium models have been very successful at describing the physical conditions in hot coronal loops (T greater than 10 exp 6 K). However, equilibrium models of cooler loops predict densities that are much lower than observed. We follow the evolution of a hot loop which undergoes a sudden reduction in heat input. The physical conditions in the cooling loop show significant departures from equilibrium. Such models appear to be able to reproduce the physical conditions observed in intermediate temperature loops (T between values of 10 exp 5 and 10 exp 6 K).