Excitation of acoustic waves by vortices in the quiet Sun - Astrophysics > Solar and Stellar AstrophysicsReport as inadecuate




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Abstract: Five-minutes oscillations is one of the basic properties of solar convection.Observations show mixture of a large number of acoustic wave fronts propagatingfrom their sources. We investigate the process of acoustic waves excitationfrom the point of view of individual events, by using realistic 3D radiativehydrodynamic simulation of the quiet Sun. The results show that the excitationevents are related to dynamics vortex tubes or swirls in the intergranularlanes. These whirlpool-like flows are characterized by very strong horizontalvelocities 7 - 11 km-s and downflows ~ 7 km-s, and are accompanied bystrong decreases of the temperature, density and pressure at the surface and ina ~ 0.5-1 Mm deep layer below the surface. High-speed whirlpool flows canattract and capture other vortices. According to our simulation results, theprocesses of the vortex interaction, such as vortex annihilation, can cause theexcitation of acoustic waves.



Author: I.N. Kitiashvili, A.G. Kosovichev, N.N. Mansour, A.A. Wray

Source: https://arxiv.org/







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