Small-scale H{\alpha} Jets in the Solar Chromosphere

TL;DR

This study uses high-resolution solar observations to analyze small-scale H-alpha jets, revealing their velocities, origins, and potential role in mass transfer from the photosphere to the corona.

Contribution

It provides detailed velocity measurements and links jet activity to underlying magnetic features, supporting the siphon flow model for these phenomena.

Findings

Jet velocities up to 45 km/s observed.

Jets originate near Ca II K brightenings and magnetic bright points.

Jets may contribute to mass outflow from the photosphere to the corona.

Abstract

High temporal and spatial resolution observations from the Rapid Oscillations in the Solar Atmosphere (ROSA) multiwavelength imager on the Dunn Solar Telescope are used to study the velocities of small-scale H{\alpha} jets in an emerging solar active region. The dataset comprises of simultaneous imaging in the H{\alpha} core, Ca II K, and G band, together with photo- spheric line-of-sight magnetograms. Time-distance techniques are employed to determine projected plane-of-sky velocities. The H{\alpha} images are highly dynamic in nature, with estimated jet velocities as high as 45 km s^{-1}. These jets are one-directional, with their origin seemingly linked to underlying Ca II K brightenings and G-band magnetic bright points. It is suggested that the siphon flow model of cool coronal loops is suitable for the interpretation of our observations. The jets are associated with small-scale explosive events, and may provide a mass outflow from the photosphere to the corona.