Spicule Dynamics over Plage Region

TL;DR

This study analyzed the dynamic properties of spicular jets in a solar plage region using high-resolution images, revealing their shorter length, ballistic motion, and deceleration patterns, with implications for understanding solar atmospheric dynamics.

Contribution

The paper introduces a new statistical analysis of plage spicule dynamics using the MadMax image processing method, providing detailed measurements of their motion and properties.

Findings

Spicular jets in plage regions are shorter than quiet Sun spicules.

Most plage spicules exhibit a rise and retreat cycle.

Deceleration correlates with initial ejection velocity.

Abstract

We studied spicular jets over a plage area and derived their dynamic characteristics using Hinode Solar Optical Telescope (SOT) high-resolution images. The target plage region was near the west limb of the solar disk. This location permitted us to study the dynamics of spicular jets without the overlapping effect of spicular structures along the line of sight. In this work, to increase the ease with which we can identify spicules on the disk, we applied the image processing method `MadMax' developed by Koutchmy et al. (1989). It enhances fine, slender structures (like jets), over a diffuse background. We identified 169 spicules over the target plage. This sample permits us to derive statistically reliable results regarding spicular dynamics. The properties of plage spicules can be summarized as follows: (1) In a plage area, we clearly identified spicular jet features. (2) They were shorter in length than the quiet region limb spicules, and followed ballistic motion under constant deceleration. (3) The majority (80%) of the plage spicules showed the cycle of rise and retreat, while 10% of them faded out without a complete retreat phase. (4) The deceleration of the spicule was proportional to the velocity of ejection (i.e. the initial velocity).