The thermal starting plume as an acoustic source

We propose that solar acoustic oscillations are excited by localized coolin g events and new downflow-plume formation at the solar surface. The excitat ion process involves, in successive stages, radiative cooling, buoyant acce leration, and advective inflow. Pressure fluctuations induced at each stage result in monopolar, dipolar, and quadrupolar acoustic emission. We examin e this excitation mechanism in detail, measure the acoustic energy output b y such events, and discuss possible observational implications for heliosei smic spectra.