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arXiv · 0907.4842

Why does the Sun's torsional oscillation begin before the sunspot cycle?

Sagar Chakraborty·Arnab Rai Choudhuri·Piyali Chatterjee
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Abstract

Although the Sun's torsional oscillation is believed to be driven by the Lorentz force associated with the sunspot cycle, this oscillation begins 2--3 yr before the sunspot cycle. We provide a theoretical explanation of this with the help of a solar dynamo model having a meridional circulation penetrating slightly below the bottom of the convection zone, because only in such dynamo models the strong toroidal field forms a few years before the sunspot cycle and at a higher latitude.

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Sagar Chakraborty, Arnab Rai Choudhuri, Piyali Chatterjee. 2009-07-28. Why does the Sun's torsional oscillation begin before the sunspot cycle?. https://doi.org/10.1103/physrevlett.102.041102

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