On the Inversion of the Baade-wesselink Technique

A general framework is given for the inversion of a "two-point" formulation of the Baade-Wesselink technique. This means that phases of equal radius are selected and used to get information regarding brightness and temperature. The inversion method is used to evaluate the surface brightness/(V -R) relation in two classical Cepheids, V482 Sco and R TrA. The slope found is consistent with previously reported values, but it is argued that the radius determinations will be very uncertain, Finally, a proposal is made for employing the B-W inversion to construct a parameterization for brightness and temperature. This leads to the determination of radii and, ultimately, of temperatures and luminosities as well.