Slow magnetoacoustic standing waves in a curved solar coronal slab

Aims. We consider a model of a two-dimensional solar coronal arcade to explore the effects of a curved magnetic field topology on excitation and attenuation of slow magnetoacoustic standing waves.Methods. The time-dependent ideal magnetohydrodynamic equations are solved numerically to find the spatial and temporal signatures of these waves.Results. A pulse in gas pressure initially launched at a loop footpoint excites the fundamental mode of slow magnetoacoustic standing waves. The typical excitation time of such a wave mode is 2.5 wave periods, with a similar attenuation timescale. These values are remarkably similar to those recovered from observations by SOHO/SUMER in an Fe XIX line.Conclusions. Slow magnetoacoustic standing waves are excited and attenuated more efficiently in curved magnetic field lines than in a straight magnetic slab topology. The waves supported by the magnetic arcade are in far closer agreement with observations.