Induced mass and wave motions in the lower solar atmosphere. I - Effects of shear motion of flux tubes

Abstract

Observations indicate that various dynamic solar phenomena lead to enhanced emission of electromagnetic waves from radio to X-ray wavelengths which can be traced to magnetic activity in the photospheric level. A number of previous investigations have ignored the dynamic responses in the solar atmosphere. On the other hand, Nakagawa et al. (1978, 1981) have studied the atmospheric responses in the frame of MHD in the supersonic super-Alfvenic region. Studies of the slowly varying dynamic response (subsonic) have been unsuccessful because of the requirements of high accuracy in the numerical scheme in which a rigorous mathematical treatment of the boundary conditions is necessary. Recently, a numerical MHD model was constructed by using the full implicit continuous eulerian method. The present investigation makes use of a method which is written in a more convenient numerical code. A two-dimensional, time-dependent, nonplanar MHD model is used to investigate the induced mass and wave motions in the lower solar atmosphere due to the shear motion of flux tubes.