ACOUSTIC-WAVE ENERGY FLUXES FOR LATE-TYPE STARS

We revisit the problem of acoustic wave generation by turbulent convec tion in late-type stellar atmospheres. Using the Lighthill-Stein theor y with modifications described in our recent paper Musielak et al, (19 94), we compute both acoustic frequency spectra and total acoustic flu xes oil basis of grey LTE mixing-length convection zone models for pop ulation I stars, in the range of effective temperatures T-eff = 2000 - 10000 K and gravities log g = 0 - 8. The turbulent flow field is repr esented by an extended Kolmogorov spatial and modified Gaussian tempor al energy spectrum. The mixing-length parameter was varied in the rang e alpha = 1 - 2. Particularly for M-dwarf stars we find large discrepa ncies between our fluxes and those of Bohn (1981, 1984), Except for ve ry cool dwarf stars our total fluxes are well reproduced by the simple Lighthill-Proudmann formula already developed in the 1950's.