A possible mechanism for enhanced absorption of p-modes in sunspot and plage regions

TLDR: In this article, the authors proposed a mechanism to explain the absorption of the p-mode (acoustic) wave power incident upon the Sun's surface, based on the idea that sunspots are assembled from many individual flux tubes with highly variant physical conditions.

Abstract: Magnetic regions on the Sun's surface are observed to absorb large fractions of the p-mode (acoustic) wave power incident upon them. We propose a mechanism to explain the absorption, based on the idea that sunspots are assembled from many individual flux tubes with highly variant physical conditions. Strong gradients in the (perturbed) parameters of a wave propagating through such an inhomogeneous medium result in enhanced absorption of the wave power. The gradients in the wave parameters occur on the scale of the background flux tubes which is smaller than the wavelength