June 29, 2012, 12:00 pm - 1:00 pm

June 29, 12:00 pm - 1:00 pm

The fundamental scales of solar coronal loops. Can we resolve them?

Dr. Ignacio Ugarte-Urra, Naval Research Laboratory/George Mason University

One of the difficulties in understanding the mechanism responsible of heating the solar corona is our inability to characterize properties like the fundamental spatial and temporal scales of that heating. Coronal loops are the building blocks of the atmosphere and understanding their properties and evolution provides invaluable clues about the mechanism responsible of their formation. A combination of spectral data from the Hinode EUV Imaging Spectrometer (EIS) and high resolution imaging from the Solar Dynamics Observatory (SDO) Atmospheric Imaging Assembly (AIA) are used to investigate the fundamental spatial scales of coronal loops. We construct multi-isothermal thread models and find that we are able to successfully reproduce the cross-loop intensity profiles observed by EIS and AIA. The models allow us to set constraints on the number of threads needed to reproduce a particular loop structure, and the results suggest that although most coronal loops remain unresolved, current instruments are close to resolving them. We discuss the implications of these results for coronal heating models.