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Transverse MHD waves permeate the solar atmosphere and are a candidate for coronal heating. However, the origin of these waves is still unclear. In this work, we analyse coordinated observations from textit{Hinode}/SOT and textit{IRIS} of a prominence/coronal rain loop-like structure at the limb of the Sun. Cool and dense downflows and upflows are observed along the structure. A collision between a downward and an upward flow with an estimated energy flux of $10^{7}-10^{8}$~erg~cm$^{-2}$~s$^{-1}$ is observed to generate oscillatory transverse perturbations of the strands with an estimated $approx40~$km~s$^{-1}$ total amplitude, and a short-lived brightening event with the plasma temperature increasing to at least $10^{5}~$K. We interpret this response as sausage and kink transverse MHD waves based on 2D MHD simulations of plasma flow collision. The lengths, density and velocity differences between the colliding clumps and the strength of the magnetic field are major parameters defining the response to the collision. The presence of asymmetry between the clumps (angle of impact surface and/or offset of flowing axis) is crucial to generate a kink mode. Using the observed values we successfully reproduce the observed transverse perturbations and brightening, and show adiabatic heating to coronal temperatures. The numerical modelling indicates that the plasma $beta$ in this loop-like structure is confined between $0.09$ and $0.36$. These results suggest that such collisions from counter-streaming flows can be a source of in-situ transverse MHD waves, and that for cool and dense prominence conditions such waves could have significant amplitudes.
Current analytical and numerical modelling suggest the existence of ubiquitous thin current sheets in the corona that could explain the observed heating requirements. On the other hand, new high resolution observations of the corona indicate that its
Characterized by cyclic axisymmetric perturbations to both the magnetic and fluid parameters, magnetohydrodynamic fast sausage modes (FSMs) have proven useful for solar coronal seismology given their strong dispersion. This review starts by summarizi
Some high-resolution observations have revealed that the active-region solar corona is filled with myriads of thin strands even in apparently uniform regions with no resolved loops. This fine structure can host collective oscillations involving a lar
We present a linear stability analysis of the perturbation modes in anisotropic MHD flows with velocity shear and strong magnetic field. Collisionless or weakly collisional plasma is described within the 16-momentum MHD fluid closure model, that take
We carry out a study of the global three-dimensional (3D) structure of the electron density and temperature of the quiescent inner solar corona ($r<1.25 R_odot$) by means of tomographic reconstructions and magnetohydrodynamic simulations. We use diff