Active chromospheric fibril singularity: Coordinated observations from Solar Orbiter, SST, and IRIS

Abstract

We report the discovery of a ‘chromospheric fibril singularity,’ a new feature observed in the solar chromosphere using coordinated observations from Solar Orbiter, the Swedish 1-m Solar Telescope (SST), and IRIS. The feature forms in a weak magnetic-field corridor between two flux concentrations of equal sign, characterized by a vertically inverted-Y-shaped field-line pattern. The observations demonstrate that this singularity acts as a site for magnetic activity, specifically in the vicinity of a blow-out solar jet and a flaring loop. We propose that converging photospheric moat flows exert pressure on this structure, leading to the formation of a current layer and subsequent magnetic reconnection.