Mesogranular structure in a hydrodynamical simulation

TL;DR

This study investigates mesogranular flow patterns in solar surface convection using hydrodynamical simulations, revealing that these patterns lack intrinsic length and time scales, and depend on analysis parameters.

Contribution

The paper demonstrates that mesogranular patterns are not characterized by intrinsic scales and depend on analysis choices, challenging previous assumptions.

Findings

Mesogranules are identified as patches of positive divergence.

Flow pattern characteristics depend on averaging time and length.

No intrinsic length or time scales are found for mesogranular patterns.

Abstract

We analyse mesogranular flow patterns in a three-dimensional hydrodynamical simulation of solar surface convection in order to determine its characteristics. We calculate divergence maps from horizontal velocities obtained with the Local Correlation Tracking (LCT) method. Mesogranules are identified as patches of positive velocity divergence. We track the mesogranules to obtain their size and lifetime distributions. We vary the analysis parameters to verify if the pattern has characteristic scales. The characteristics of the resulting flow patterns depend on the averaging time and length used in the analysis. We conclude that the mesogranular patterns do not exhibit intrinsic length and time scales.