Active region jets on August 25, 2011

Jasmina Magdalenic, Royal Observatory of Belgium

Solar coronal jets are impulsive, collimated features, observed at different energies. Jets are seen on the Sun at all scales - from those occurring in coronal holes to those in active regions. The process of creating jets is mostly considered to be related to reconnection between open and closed field lines. This study is focused on the active region jets which occur regularly at small-scale, but can also occur on a larger scale related to CMEs and SEPs. The aim of the study is to determine why the jets occurred in this particular active region, what their dynamics are, and possibly to predict what we might see with Solar Orbiter. Understanding the process of jets requires spectral and imaging data across different energy regimes. Therefore, we selected well observed series of jets which occurred on August 25, 2011, in the active region NOAA 1271 (located near the western solar limb). First results of the multiwavelength study show that the repeated jets observed on August 25, originate from the western part of the active region and were associated with a small flux emergence. Due to the existence of open field lines but also a large transequatorial loop system (closed field lines), some of the type III radio bursts associated with jets propagated to the interplanetary space and some did not. In the first radio triangulation study of radio emission associated with jets, we employed goniopolarimetric measurements taken simultaneously from STEREO A and WIND spacecraft. The reconstructed propagation paths of the interplanetary type III bursts associated with jets indicate that the fast electron beams are propagating towards the Earth, but the path does not completely coincide with the Parker spiral. This deviation in the propagation path of the electron beams associated with jets is probably due to the influence of a nearby coronal hole.