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arXiv · 2110.13952

Changes in the near-surface shear layer of the Sun

H. M. Antia·Sarbani Basu
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Abstract

We use helioseismic data obtained over two solar cycles to determine whether there are changes in the near-surface shear layer (NSSL). We examine this by determining the radial gradient of the solar rotation rate. The radial gradient itself shows a solar-cycle dependence, and the changes are more pronounced in the active latitudes than at adjoining higher latitudes; results at the highest latitudes (greater than about70 degrees) are unreliable. The pattern changes with depth, even within the NSSL. We find that the near-surface shear layer is deeper at lower latitudes than at high latitudes and that the extent of the layer also shows a small solar-cycle related change.

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H. M. Antia, Sarbani Basu. 2021-10-26. Changes in the near-surface shear layer of the Sun. https://doi.org/10.3847/1538-4357/ac32c3

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