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Solar coronal observations at high frequencies

A. C. Katsiyannis·M. Mathioudakis·K. J. H. Phillips·D. R. Williams·F. P. Keenan
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Abstract

The Solar Eclipse Coronal Imaging System (SECIS) is a simple and extremely fast, high-resolution imaging instrument designed for studies of the solar corona. Light from the corona (during, for example, a total solar eclipse) is reflected off a heliostat and passes via a Schmidt-Cassegrain telescope and beam splitter to two CCD cameras capable of imaging at 60 frames a second. The cameras are attached via SCSI connections to a purpose-built PC that acts as the data acquisition and storage system. Each optical channel has a different filter allowing observations of the same events in both white light and in the green line (Fe XIV at 5303 A). Wavelet analysis of the stabilized images has revealed high frequency oscillations which may make a significant contribution on the coronal heating process. In this presentation we give an outline of the instrument and its future development.

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A. C. Katsiyannis, M. Mathioudakis, K. J. H. Phillips, D. R. Williams, F. P. Keenan. 2001-11-22. Solar coronal observations at high frequencies. https://arxiv.org/abs/astro-ph/0111447

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