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arXiv · 2309.11787

Dependence of Solar supergranular lifetime on surface magnetic activity and rotation

Sowmya G. M.·Rajani G.·U. Paniveni·R. Srikanth
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Abstract

The lifetimes and length-scales for supergranular cells in active and quiescent regions of the Solar chromosphere, and the relation between the two, were studied using a time series of Ca II K filtergrams. The lifetimes, in contrast to supergranular length scale and fractal dimension, show no significant dependence on Solar latitude, suggesting that cell lifetimes are independent of the differential rotation and a possible supergranular super-rotation. The functional form of the relation was obtained guided by a comparison of the distributions of the two supergranular parameters. We infer a linear dependence of cell lifetime on area, which can be understood by the assumption of the network's evolution via a diffusion of the magnetic field. Our analysis suggests that the diffusion rate in quiet regions is about 10% greater than in active regions.

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Sowmya G. M., Rajani G., U. Paniveni, R. Srikanth. 2023-09-21. Dependence of Solar supergranular lifetime on surface magnetic activity and rotation. https://arxiv.org/abs/2309.11787

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