Can the Differential Emission Measure Constrain the Timescale of Energy Deposition in the Corona?
|Titre||Can the Differential Emission Measure Constrain the Timescale of Energy Deposition in the Corona?|
|Type de publication||Journal Article|
|Year of Publication||2013|
|Auteurs||Guennou, C, Auchere, F, Klimchuk, JA, Bocchialini, K, Parenti, S|
|Journal||The Astrophysical Journal|
|Date Published||September 1, 2013|
|Mots-clés||plasmas, Sun: corona, Sun: UV radiation, techniques: spectroscopic|
In this paper, the ability of the Hinode/EIS instrument to detect radiative signatures of coronal heating is investigated. Recent observational studies of active region cores suggest that both the low and high frequency heating mechanisms are consistent with observations. Distinguishing between these possibilities is important for identifying the physical mechanism(s) of the heating. The differential emission measure (DEM) tool is one diagnostic that allows us to make this distinction, through the amplitude of the DEM slope coolward of the coronal peak. It is therefore crucial to understand the uncertainties associated with these measurements. Using proper estimations of the uncertainties involved in the problem of DEM inversion, we derive confidence levels on the observed DEM slope. Results show that the uncertainty in the slope reconstruction strongly depends on the number of lines constraining the slope. Typical uncertainty is estimated to be about ±1.0 in the more favorable cases.