Kink waves in an active region dynamic fibril

TL;DR

This paper reports high-resolution observations of a kink wave in a chromospheric fibril, estimating magnetic field strength and suggesting it was triggered by a small-scale reconnection event.

Contribution

It provides detailed measurements of kink wave properties in an active region fibril and links wave activity to magnetic field strength and possible reconnection triggers.

Findings

Kink wave properties similar to off-limb spicules

Estimated magnetic field strength of a few hundred Gauss

Wave triggered by small-scale reconnection event

Abstract

We present high spatial and temporal resolution Ca II 8542 observations of a kink wave in an on-disk chromospheric active region fibril. The properties of the wave are similar to those observed in off-limb spicules. From the observed phase and period of the wave we determine a lower limit for the field strength in the chromospheric active region fibril located at the edge of a sunspot to be a few hundred Gauss. We find indications that the event was triggered by a small-scale reconnection event higher up in the atmosphere.