| Popis: |
We assess the current state of several areas in Cepheid research. The problem of mass determination is discussed and a number of methods evaluated. wE examine a recent interpretation of Cepheid masses which adopts a “short” distance scale and relies heavily on the Baade-Wesselink technique. This interpretation requires an evolutionary dichotomy, and is criticized on the basis of the great regularity observed among Cepheid light curves. The homogeneity of the Cepheid sample is further invoked to argue against the introduction of physical mechanisms which increase the complexity of stellar evolution. We touch briefly on the question of opacity and mention some benefits which would be derived from an increase in absorption by heavy elements. Finally, we discuss the implications (“long” distance scale and “cool” temperature calibration) arising from the recent determination of the mass of SU Cyg from its orbit. The importance of verifying this mass is emphasized. |
