Abstract
The directional dependence of the emission of sound waves in the solar atmosphere is studied. It is shown that quadrupole acoustic radiation generated in convective turbulence is strongly enhanced in the direction of the mean convective flow. The intensity in a direction θ with the convective velocity is proportional to (1 − M c cosθ)−17/2, where M c is the Mach number of the convective motion. The influence of the atmospheric cut off frequency on the transmitted acoustic spectrum is taken into account. It is suggested that low frequency atmospheric oscillations may modulate the flux of high frequency sound waves.
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Kuperus, M. On the directional dependence of the emission of acoustic noise by convective turbulence in a gravitational atmosphere. Sol Phys 22, 257–262 (1972). https://doi.org/10.1007/BF00148694
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DOI: https://doi.org/10.1007/BF00148694