Evolution of Weak Perturbations Excited at the Footpoint of a Coronal Loop: Effect of Thermal Misbalance on Magnetoacoustic and Entropy Modes

The paper examines the evolution of weak perturbations excited at the boundary of a “warm” coronal loop in a strong magnetic field. The primary focus is on the effect of thermal misbalance caused by heating and radiative cooling processes on the dispersion properties and energy distribution between slow magnetoacoustic and entropy modes. An exact analytical solution to the boundary value problem is obtained using the Fourier method and Duhamel’s principle, allowing one to analyze the dependence of the energy distribution on the characteristic times of the thermal misbalance. It is shown that local heating and cooling parameters determine not only the phase velocities and wave decrements but also the initial energy contribution of each mode. The obtained results can be used to interpret observational data and diagnose plasma parameters in the solar corona.