Astrophysics Research Centre

• Submitted by: Louise Harra
• Authors: L. K. Harra, D. Baker, A. Sterling, S. Edwards, H. Hara, R. Howe, L. van Driel-Gesztelyi
• Session: Monday afternoon posters.

We explore the changes in coronal non-thermal velocity (Vnt) measurements at the poles from solar minimum to solar maximum using Hinode EUV Imaging Spectrometer data. We find that although the intensity in the corona at the poles does tend to increase with the cycle, there are no significant changes in the Vnt values. Combining these results with magnetic modelling indicates that the magnetic structures that create the enhanced Vnt behaviour are small-scale features and hence not easily measurable at the poles. Because they do not change during the solar cycle, they are likely to be created by a local dynamo. We explore in detail some individual examples to study the interaction of features within the coronal holes and at the boundaries.

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