OBSERVATIONAL SEARCHES FOR SOLAR g-MODES: SOME THEORETICAL CONSIDERATIONS

We argue that the solar g-modes are unlikely to have caused the discrete peaks in the power spectrum of the solar wind flux observed by Thomson et al (1995). The lower limit to the energy of individual g-modes, using the amplitudes given by Thomson et al., is estimated to be at least 10 ergs for low-order g-modes; the resulting surface velocity amplitude is at least 50 cm s, larger than the observational upper limit (5 cm s). We suggest that the most likely source for the excitation of solar g-modes is turbulent stresses in the convection zone. The surface velocity amplitude of low-degree and low-order g-modes resulting from this process is estimated to be of order 10 cm s. This amplitude is interestingly close to the detection threshold of the SOHO satellite. The long lifetime of g-modes (110 yr for low-order modes) should be helpful in detecting these small-amplitude pulsations. Subject headings: Sun: interior— Sun: oscillations