Hi-C 2.1 Observations of Reconnection Nanojets

Abstract

One of the possible mechanisms for heating the solar atmosphere is the magnetic reconnection occurring at different spatiotemporal scales. The discovery of fast bursty nanojets due to reconnection in the coronal loops has been linked to nanoflares and is considered as a possible mechanism for coronal heating. The occurrence of these jets mostly in the direction inwards to the loop was observed in the past. In this study, we report 10 reconnection nanojets, four with directions inward and six moving outward to the loop, in observations from the High-resolution Coronal Imager 2.1 and the Atmospheric Imaging Assembly (AIA) on board the Solar Dynamics Observatory. We determined the maximum length, spire width, speed, and lifetimes of these jets and studied their correlations. We found that outward jets with higher speeds are longer in length and duration while the inward jets show opposite behavior. The average duration of the outward jets is ≈42 s and that of inward jets is ≈24 s. We identified jets with subsonic speeds below 100 km s−1 to high speeds over 150 km s−1. These jets can be identified in multiple passbands of AIA extending from the upper transition region to the corona suggesting their multithermal nature.