Dependence of Solar supergranular lifetime on surface magnetic activity and rotation

TL;DR

This study investigates how the lifetimes of solar supergranular cells relate to magnetic activity and rotation, revealing that lifetimes are independent of latitude and depend linearly on cell area, with diffusion rates varying between active and quiet regions.

Contribution

It provides the first detailed analysis of supergranular lifetime dependence on magnetic activity and surface dynamics, highlighting a linear relationship with cell area and differences in diffusion rates.

Findings

Supergranular lifetimes are independent of solar latitude.

Cell lifetime has a linear dependence on area.

Diffusion rate is about 10% higher in quiet regions.

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.