Vector magnetic fields of Solar Granulation

TL;DR

This study statistically analyzes the vector magnetic fields of solar granulation using Hinode SOT/SP observations, revealing detailed magnetic and velocity properties of granules and their differences from intergranular lanes.

Contribution

It introduces a comprehensive statistical approach to characterize the magnetic fields of solar granulation and reconstructs average granular cells for detailed magnetic flux distribution analysis.

Findings

Magnetic flux densities vary significantly between granules and intergranular lanes.

A linear correlation exists between intensity and Doppler velocity in granules.

Average magnetic properties of granulation differ from those of abnormal granules.

Abstract

Observations of quiet Sun from the Solar Optical Telescope/Spectro-Polarimeter (SOT/SP) aboard the Hinode spacecraft would reveal the magnetic characters of the solar photosphere. By making use of the deep mode observations of three quiet regions, we have statistically studied the vector magnetic fields of solar granulation. More than 2000 normal granules are manually selected to form a sample. It is recognized that some granules are even darker than the mean photosphere in intensity, and there is a linear correlation between intensity and Doppler velocity in granules. The distributions of longitudinal and transverse apparent magnetic flux densities, Doppler velocity and continuum intensity of granules are obtained, and their unsigned magnetic flux measured. Two approaches are carried out in this study. First we obtained the magnetic properties of granulation by averaging the measurements for all the sampling granules. Secondly, we reconstructed an average granular cell based on a sub-sample, and obtained the detailed distribution of apparent magnetic flux density within the model granular cell. All the results have been compared with that of inter-granular lanes and a few typical abnormal granules.