Exploring the Dynamics of Near-Surface Solar Convection with Helioseismology
Author | |
Abstract |
<p>I present a new implementation of local helioseismology along with observations of near-surface solar\ <span style="line-height: 1.6em;">convection made with this method. The upper 5\% of the solar radius (35 Mm) is known as the Near-Surface\ </span><span style="line-height: 1.6em;">Shear Layer (NSSL) and is characterized by strong rotational shear. While the physical origin of this layer\ </span><span style="line-height: 1.6em;">remains unknown, current theories point to convective motions playing an important role. In this thesis I\ </span><span style="line-height: 1.6em;">investigate the properties of convection in the NSSL using a newly-developed high-resolution ring-diagram\ </span><span style="line-height: 1.6em;">analysis. I present measurements of the speeds and spatial scales of near-surface flows and from these infer\ </span><span style="line-height: 1.6em;">that the degree of rotational constraint on convective flows varies significantly across this layer. In depth\ </span><span style="line-height: 1.6em;">analysis of the convective patterns reveals the pervasive influence of coherent downflow plumes generated at\ </span><span style="line-height: 1.6em;">the photosphere. These structures link the convective pattern of supergranulation seen in surface observations\ </span><span style="line-height: 1.6em;">with the deeper motions found within the NSSL and further hint at the importance of rotation in this layer.</span></p>
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Year of Publication |
2015
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Degree |
Ph.D.
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Number of Pages |
202
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Date Published |
12-2015
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University |
University of Colorado Boulder
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City |
Boulder, CO
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JILA PI Advisors | |
greer_thesis_nov23.pdf18.99 MB
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Publication Status |