The Nature of High-frequency Oscillations Associated with Short-lived Spicule-type Events

We investigate high-resolution spectroscopic and imaging observations from the CRisp Imaging SpectroPolarimeter (CRISP) instrument to study dynamics of chromospheric spicule-type events. It is widely accepted that fine structures are waveguides for several types magnetohydrodynamic (MHD) oscillations, which can transport energy lower upper layers Sun. provide a statistical 30 high-frequency waves associated with These oscillations have two components transverse motions: plane-of-sky (POS) motion line-of-sight (LOS) motion. focus on single isolated spicules track POS using time–distance analysis in LOS direction Doppler information. use moment find relation between motions. The composition these motions suggests wave has helical structure. do not phase differences points along This may be result oscillation being standing mode, or propagation mostly perpendicular direction. There evidence fast magnetoacoustic fronts propagating across structures. To conclude, we hypothesize compression rarefaction passing influence appearance events, only by contributing moving them out wing spectral line but also through creation density enhancements an increase opacity H? line.