Measuring kink waves in the quiescent chromosphere.
Krishna Mooroogen
Northumbria University
Richard Morton (Northumbria University)
Magneto-hydrodynamic (MHD) oscillations, originating from convective motions within the photosphere of the Sun, have seen to be ubiquitous in the solar atmosphere. MHD oscillations have been detected as early as the 1960’s and have been hypothesised to play a significant role in atmospheric heating. In particular, Alfvén-like waves appear to be a suitable candidate for the energy transport associated with atmospheric heating. This is due to their ability to traverse over the several layers of the stratified atmosphere, however they have been difficult to detect as they cause small-scale perturbations of the fine structure. Recent high-resolution instruments have begun to change this picture.

In this study we examine the wave properties of fibrils in the H-alpha quiescent solar chromosphere using the ground based Swedish Solar Telescope (SST) CRISP instrument. With the intention of looking for kink-wave signatures with perpendicular polarisations, we create time series plots of both intensity and velocity measurements. Periodic displacements of the fibrils axis are observed along with periodic variations in Doppler velocity. We measure the amplitude, period and phase velocity of the waves. Furthermore, we model the noise from the instrument to improve the uncertainties of the measurement.