Transverse Motions of Chromospheric Type II Spicules Observed by the New Solar Telescope

TL;DR

This study uses high-resolution solar data to analyze transverse motions of type II spicules, revealing kink features, coherent oscillations, and high-frequency waves likely caused by magnetic reconnection.

Contribution

It provides new observational evidence linking type II spicule motions and oscillations to magnetic reconnection and kink mode waves.

Findings

Type II spicules show kink and inverse 'Y' features.

Coherent transverse motions and high-frequency oscillations are detected.

Oscillation periods range from 30 to 180 seconds, averaging 90 seconds.

Abstract

Using high resolution off-band \ha\ data from the New Solar Telescope and Morlet wavelet analysis technique, we analyzed transverse motions of type II spicules observed near the North Pole of the Sun. Our new findings are that i) some of the observed type II spicules display kink or an inverse "Y" features, suggesting that their origin may be due to magnetic reconnection, and ii) type II spicules tend to display coherent transverse motions/oscillations. Also, the wavelet analysis detected significant presence of high frequency oscillations in type II spicules, ranging from 30 to 180 s with the the average period of 90 s. We conclude that at least some of type II spicules and their coherent transverse motions may be caused by reconnection between large scale fields rooted in the intergranular lanes and and small-scale emerging dipoles, a process that is know to generate high frequency kink mode MHD waves propagating along the magnetic field lines.