Slow magnetoacoustic waves in coronal loops

A theoretical model interpreting propagating disturbances of EUV emission i ntensity, recently observed in coronal loops, is constructed in terms of sl ow magnetoacoustic waves. The model is one-dimensional and incorporates eff ects of nonlinearity, dissipation due to finite viscosity and thermal condu ction, and gravitational stratification of plasma in the loop. It has been found that, for the observationally detected parameters of the waves, the m ain factors influencing the wave evolution are dissipation and stratificati on. The upwardly propagating waves of observed periods (5-20 min) are found to decay significantly in the vicinity of the loop apex, explaining the ra rity of observational detection of downwardly propagating waves. The model provides a theoretical basis for development of MHD seismology of the coron al loops.