Observational features of equatorial coronal hole jets

TL;DR

This study analyzes equatorial coronal hole jets using STEREO data, revealing their main features, velocities, and durations, and suggests they are physically similar to polar coronal hole jets.

Contribution

First observational analysis of equatorial coronal hole jets, comparing their features to polar jets and providing velocity and duration measurements.

Findings

Average jet visibility time is about 30 minutes.

Uplift velocity for one event is about 200 km/s.

Deceleration rate is about 0.11 km/s², less than solar gravity.

Abstract

Collimated ejections of plasma called "coronal hole jets" are commonly observed in polar coronal holes. However, such coronal jets are not only a specific features of polar coronal holes but they can also be found in coronal holes appearing at lower heliographic latitudes. In this paper we present some observations of "equatorial coronal hole jets" made up with data provided by the STEREO/SECCHI instruments during a period comprising March 2007 and December 2007. The jet events are selected by requiring at least some visibility in both COR1 and EUVI instruments. We report 15 jet events, and we discuss their main features. For one event, the uplift velocity has been determined as about 200 km/s, while the deceleration rate appears to be about 0.11 km/s2, less than solar gravity. The average jet visibility time is about 30 minutes, consistent with jet observed in polar regions. On the basis of the present dataset, we provisionally conclude that there are not substantial physical differences between polar and equatorial coronal hole jets.