THE PROSPECTS FOR ASTEROSEISMOLOGY FROM GROUND-BASED SITES

We reexamine the possibility of detecting p-mode oscillations in Sun-l ike stars with ground-based telescopes. Previous attempts to make such observations with photometric techniques have been limited to subgian t stars in M67 and have illustrated the great difficulties involved in performing ground-based asteroseismology, Substantial gains in observ ing efficiency can be realized from new diagnostic techniques and impr ovements in instrumentation, especially with new CCD camera systems. W e show that for appropriately selected field stars observed with a net work of telescopes or at a high-duty-cycle site, it will be possible t o detect p-mode oscillations from the ground. An alternative to a netw ork of telescopes for asteroseismology would be to develop a dedicated observatory for this purpose at a high-duty-cycle site, i.e., the Sou th Pole. We estimate the scintillation, the main noise source in aster oseismology, at the Pole by modeling the index of refraction structure parameter from meteorological data. The model results show that at th e Pole the variance of the relative intensity fluctuations-i.e., the s cintillation-should be a factor of 5 smaller than at Mauna Kea, Taking into account the improvements possible with target selection and inst rumentation, the South Pole would be an excellent site for asteroseism ological work on Sun-like stars.