Evolution of helicity in NOAA 10923 over three consecutive solar rotations

TL;DR

This study tracks the evolution of magnetic helicity and chirality in NOAA active region 10923 over three solar rotations, comparing properties across different solar atmospheric heights and linking photospheric, chromospheric, and coronal features.

Contribution

It provides a detailed multi-height analysis of magnetic chirality evolution in a single active region over multiple rotations, integrating observations from various solar instruments.

Findings

Chirality is consistent across photospheric, chromospheric, and coronal heights.

Twistedness of superpenumbral filaments persists in photospheric transverse fields.

Chirality at different heights shows correlated evolution.

Abstract

We have studied the evolution of magnetic helicity and chirality in an active region over three consecutive solar rotations. The region when it first appeared was named NOAA10923 and in subsequent rotations it was numbered NOAA 10930, 10935 and 10941. We compare the chirality of these regions at photospheric, chromospheric and coronal heights. The observations used for photospheric and chromospheric heights are taken from Solar Vector Magnetograph (SVM) and H_alpha imaging telescope of Udaipur Solar Observatory (USO), respectively. We discuss the chirality of the sunspots and associated H_alpha filaments in these regions. We find that the twistedness of superpenumbral filaments is maintained in the photospheric transverse field vectors also. We also compare the chirality at photospheric and chromospheric heights with the chirality of the associated coronal loops, as observed from the HINODE X-Ray Telescope.