EUV jets, type III radio bursts and sunspot waves investigated using SDO/AIA observations

TL;DR

This study links EUV jets and type III radio bursts to sunspot activity, revealing that jets originate from the sunspot edge and are influenced by sunspot waves, with implications for understanding solar energetic events.

Contribution

It provides new observational evidence connecting sunspot waves, EUV jets, and radio bursts, highlighting the role of the sunspot edge in jet formation.

Findings

EUV jets correlate with type III radio bursts and sunspot brightening.

Jets originate along a current sheet at the sunspot edge.

Sunspot running penumbral waves influence jet footpoint brightening.

Abstract

Images from the Solar Dynamics Observatory (SDO) at 211A are used to identify the solar source of the type III radio bursts seen in WIND/WAVES dynamic spectra. We analyse a 2.5 hour period during which six strong bursts are seen. The radio bursts correlate very well with the EUV jets coming from the western side of a sunspot in AR11092. The EUV jet emission also correlates well with brightening at what looks like their footpoint at the edge of the umbra. For 10-15 min after strong EUV jets are ejected, the footpoint brightens at roughly 3 min intervals. In both the EUV images and the extracted light curves, it looks as though the brightening is related to the 3-min sunspot oscillations, although the correlation coefficient is rather low. The only open field near the jets is rooted in the sunspot. We conclude that active region EUV/X-ray jets and interplanetary electron streams originate on the edge of the sunspot umbra. They form along a current sheet between the sunspot open field and closed field connecting to underlying satellite flux. Sunspot running penumbral waves cause roughly 3-min jet footpoint brightening. The relationship between the waves and jets is less clear.