A plea for reexamining heavy element opacities in stars

Abstract

It is shown that increasing the opacity due to heavy elements by a factor of 2-3 leads to classical Cepheid models which reproduce observed period ratios at evolutionary masses and luminosities. Thus the mass anomalies are removed in both the double-mode and bump Cepheid regimes. The proposed increases may also serve to energize Beta Cephei variables, thus solving yet another important problem in the theory of pulsating stars. It is argued that opacity changes of this order are not implausible, and further work in this important area is urged.