Astrophysicists from nineteen countries met in Cambridge in April 1969 to consider the theory and observation for normal stellar atmospheres. The Proceedings contain not only the invited reviews and contributed papers but also the discussions. In addition, the book contains physical and spectral data for a reference set of sixty-eight stellar atmospheres in the effective temperature range from 4000° to 50,000°.
The principal review papers include “Properties of Synthetic Spectra and Their Sensitivity to Uncertainties of the Physical Theory” by Stephen Strom, Smithsonian Astrophysical Observatory; “The Empirical Basis of Quantitative Spectral Classification” by Charles Whitney, Smithsonian Astrophysical Observatory; “The Comparison of Synthetic Spectra with Real Spectra” by Roger Cayrel, Observatoire de Paris; and “Astronomical Problems Influencing the Selection of Parameters for Model Stellar Atmospheres” by Bengt Strömgren, Copenhagen Observatory.
A major goal of the conference was to discuss the extent to which quantitative spectral classification can be interpreted by theoretical model stellar atmospheres. Both theoreticians and observers met in an endeavor to examine more effectively the discrepancies between predictions and observations, while preserving the original flavor of the conference, has in many instances been updated and revised as a result of work growing out of the conference.
In a final session the delegates hammered out specifications for a reference grid of model atmospheres; this fundamental set for a wide range of temperatures and gravities has been computed at the Smithsonian Astrophysical Observatory and forms an important part of these Proceedings. For the cooler stars, inclusion of convection and line blanketing has produced a grid considerably more sophisticated than any previously attempted.
