Coronal Loop Heating by Nanoflares: The Impact of the Field‐aligned Distribution of the Heating on Loop Observations

Abstract

Nanoflares occurring at subresolution strands with repetition times longer than the coronal cooling time are a promising candidate for coronal loop heating. To investigate the impact of the spatial distribution of the nanoflare heating on loop observables, we compute hydrodynamic simulations with several different spatial distributions ( uniform, loop top, randomly localized, and footpoint). The outputs of the simulations are then used to calculate density and temperature diagnostics from synthetic TRACE and SXT observations. We find that the diagnostics depend only weakly on the spatial distribution of the heating and therefore are not especially useful for distinguishing among the different possibilities. Observations of the very high temperature plasmas that are present only in the earliest stages of nanoflares can shed more light on the field-aligned distribution of the heating.