Chromospheric jets around the edges of sunspots

TL;DR

This study investigates chromospheric jets at sunspot edges, revealing their role in supplying mass and energy to the corona, with jets reaching speeds up to 100 km/s and heating plasma to about 0.1 MK.

Contribution

It provides observational evidence of continuous chromospheric jets contributing to active region heating and mass transfer, highlighting their dynamic properties and potential role in coronal heating.

Findings

Jets reach speeds of 10-100 km/s

Jets heat plasma to approximately 0.1 MK

Jets may provide steady heating to active regions

Abstract

Evidence is beginning to be put forward that demonstrates the role of the chromosphere in supplying energy and mass to the corona. We aim to assess the role of chromospheric jets in active region dynamics. Using a combination of the Hinode/SOT Ca II H and TRACE 1550 {\AA} and 1600 {\AA} filters we examine chromospheric jets situated at the edge of a sunspot. Analysis reveals a near continuous series of jets, that raise chromospheric material into the low corona above a sunspot. The jets have average rise speeds of 30 km\,s^{-1} and a range of 10-100km\,s^{-1}. Enhanced emission observed at the jets leading edge suggests the formation of a shock front. Increased emission in TRACE bandpasses above the sunspot and the disappearance of the jets from the Ca II filter suggests that some of the chromospheric jet material is at least heated to \sim0.1MK. The evidence suggests that the jets could be a mechanism which provides a steady, low-level heating for active region features.