SIMBAD references

The luminosities, effective temperatures, and metallicities that are derived empirically by Kovács & Jurcsik from the light curves of a large number of globular cluster and field RRab and RRc stars are compared to theoretical RR Lyrae models. The strong luminosity dependence of the empirical blue and red edges (logL vs. logT_eff diagram) is in disagreement with that of both radiative and convective models. A reexamination of the theoretical uncertainties in the modeling leads us to conclude that the disagreement appears irreconcilable.