Presentation #111.01 in the session Mini-Filaments, Jets, Microflares, and the Heliosphere.
Solar jets of all sizes are magnetically channeled narrow eruptive events. They are often observed in UV, EUV, and coronal X-ray images. Here we present the detailed analysis of a coronal jet and the minifilament eruption that made it, fully captured and well-resolved in high-resolution IRIS Mg II spectra. The Mg II spectroheliograms show that the minifilament plasma temperature is chromospheric. The Mg II spectra show that the erupting minifilament’s plasma has blueshifted upflow in the onset of the jet spire and simultaneous redshifted downflow at the location of the compact jet bright point (JBP). From co-aligned IRIS Mg II spectroheliograms, HMI magnetograms, and AIA coronal EUV images, we find that (i) in a coronal hole, a minifilament forms above a flux-cancelation neutral line at the edge of a negative-polarity network flux clump; (ii) during the onset of the minifilament’s eruption, the JBP appears over the flux cancelation neutral line. From IRIS2 inversion of the Mg II spectra, the JBP’s Mg II bright plasma has electron density, temperature, and downward (redshift) Doppler speed of 1012 cm−3, 6000 K, and 10 km s−1, respectively. We conclude that magnetic flux cancelation builds a minifilament-carrying twisted flux rope and triggers the jet-generating eruption of the flux rope.