| Presentation Title: | How does the heating frequency on elemental strands change as a function of active region age? |
| Author(s): | Will Barnes, Stephen Bradshaw, Nicholeen Viall, Emily Mason |
Abstract:
The evolution of active regions over their lifetime, from initial emergence to the eventual complete dispersal of magnetic flux, has been well studied. However, how this evolution is connected to the detailed heating processes within an active region has been largely unexplored. In particular, it is not well known how the heating frequency on individual elemental strands within an active region is connected to the large-scale evolution of the active region.
To address this question, we study two active regions, NOAA 11190 and 11339, over two rotations using observations from SDO/AIA, Hinode/EIS, and Hinode/XRT. We compute both the emission measure distribution and the time lag in order to diagnose the underlying heating frequency and its spatial distribution over the whole active region. Additionally, we make comparisons to forward-modeled observables from synthetic images composed of ensembles of field-aligned hydrodynamic models for several different heating frequencies.
We also assess the ability of soft x-ray measurements from future observatories to diagnose these heating properties. In doing so, we are able to quantitatively assess how the spatial distribution of heating frequency over these active regions changes as they evolve and how this is connected to bulk properties of the active region such as the total unsigned magnetic flux.