On the observations of multiple MHD oscillations in the solar loops

Abstract

Observations of multiple oscillations of various magnetohydrodynamic (MHD) modes may play crucial role in the diagnostics of the local plasma conditions of solar loops. Magnetically structured coronal loops anchored into the photosphere exhibit various kinds of MHD oscillations such as fast sausage, kink, slow acoustic oscillations etc. Exploiting various harmonics of such observed MHD oscillations may be a tracer of important local plasma conditions and structuring, e.g. scale heights and signature of stratification, equilibrium condition, characteristic speed, density contrast, loop expansion factor/magnetic field divergence etc, which can shed new light on the dynamics of the solar loops. In this review, I briefly summarize the first observational signatures of multiple MHD oscillations in various types of solar loops and discuss their significance in diagnosing the solar atmosphere.