Excitation mechanisms of solar oscillations
Excitation mechanisms of solar oscillations are reviewed. Two excitation mechanisms have been proposed for solar p-mode oscillations: the linear overstability due to the so-called κ-mechanism and the stochastic excitation by turbulent convection. Here we discuss the stochastic excitation mechanism in a greater detail because it is more likely to be the possible explanation than the former mechanism. In this mechanism, the amplitudes of oscillations are determined by the balance of the excitation rate by turbulent convection to the damping rate. We examine these two effects separately. In particular, we discuss the acoustic energy generation by turbulent convection and the question of quadrupole versus dipole radiation.
KeywordsAcoustic Radiation Acoustic Power Excitation Mechanism Turbulent Convection Solar Convection Zone
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