| Popis: |
New Research Initiatives Program W-318 was successfully completed with the calculation of a series of nonlinear Cepheid models with the new DYN code. The dynamical zoning feature of the DYN code makes it unique in that it allows reliable light curves, as well as velocity curves, to be calculated. The models are used to extend to light curves Christy's conclusion, based on velocity curves, that the observations of Cepheids cannot be matched unless the mass is significantly reduced (assuming a homogeneous composition). An examination of results also leads to the conclusion that observed light curves are considerably more complex than has previously been thought. The light and velocity curves we have calculated should be useful guides for interpreting the observations. 36 references. |
