Unifying the Steady and Transient Solar Corona

The high energy XUV radiation from the Sun, with known space-weather and climate impacts, is emitted due to the presence of its higher temperature upper atmosphere, the corona (>1~MK). The problem of coronal heating is one of the longer remaining mysteries in our solar system and beyond, despite the advancements in the observational and modeling capabilities. The existence of the high temperature corona has been attributed to a combination of both steady and transient heating. The steady background heating may be a cumulative effect of a large number of unresolved transient events. Here, we demonstrate for the first time, that both the steady and transient components in an active region can be produced with a large number of heating events generated from from a single power law distribution. We use Enthalpy-based thermal evolution of loops (EBTEL), based on 0D hydrodynamical description of coronal loops, to model the emission obtained from the Atmospheric Imaging Assembly (AIA) and Focusing Optics X-ray Solar Imager (FOXSI) for an isolated loop complex from active region 12230, which resulted in a sub-A-class event from the active region. We study the parameter space characterizing the slope of the power-law distribution, along with the maximum and minimum energies that can be dissipated in an event. Our results demonstrate that the joint AIA and FOXSI-2 observations are best explained as scale-free power-laws of heating events with slopes of <~ 2 and covering a dynamic range of 7-9 orders of magnitude in energy.