Problems of Calibration of Absolute Magnitudes and Temperature of Stars : Held in Geneva, Switzerland, September 12-15, 1972

In connection with arranging IAU Symposium No. 50 on 'Spectral Classification and Multicolour Photometry', sponsored by Commissions 45 and 25, it was decided to exclude all calibration problems. Instead it was agreed that we should attempt to arrange a separate symposium, dealing with the fundamental problems of the cali­ bration of absolute magnitudes and temperatures of stars. The Executive Committee of the IAU accepted our proposal, and IAU Symposium No. 54 was held in Geneva on September 12-15, 1972, sponsored by thefollowing IAU Commissions: 24, 25, 29, 33, 35, 37,44 and 45. It was attended by about 90 scientists representing 16 countries. The Symposium was divided into eight sessions. Each session started with a review paper by an invited speaker; this was followed by a general discussion including a few contributed papers. The contents of the present volume follow closely the programmes of the individual sessions of the Symposium. Most of the recorded discussions have been kept, and only in a few cases have the order of questions and comments been altered so as to obtain more homogeneity in the presentation. Front Matter....Pages I-X Front Matter....Pages 1-1 Absolute Magnitudes from Trigonometric and Statistical Parallaxes....Pages 3-10 The Determination of Absolute Magnitudes from Proper Motions....Pages 11-17 Note on Absolute Magnitudes in the Red and Infrared of Late M-Type Dwarfs....Pages 18-20 Magnitude Absolue Moyenne Des RR Lyrae....Pages 21-22 A Program to Determine an Accurate Trigonometric Parallax for the Hyades Cluster....Pages 23-24 Front Matter....Pages 25-25 Attempt to Apply the U B V B 1 B 2 V 1 G Photometry to the Determination of the Distance of the Hyades....Pages 27-30 A Far-Ultraviolet Flux Difference Between Hyades and Pleiades Stars....Pages 31-35 Photo-Electric Measures of Hα and H β in the Scorpio-Centaurus Association....Pages 36-40 Rotational Effects on the Photometric Determinations of Absolute Magnitudes for A- and F-Type Stars....Pages 41-43 Front Matter....Pages 45-45 The Calibration of Luminosity Criteria....Pages 47-56 Absolute Magnitudes and Colours of Field Giant Branch Stars....Pages 57-63 On the K-Line Width-Absolute Magnitude Relation....Pages 64-67 Luminosity Calibration of Giants and Supergiants, G0-M5....Pages 68-77 Calibration En Magnitudes Absolues De La Classification BCD. Application à La Détermination Du Module De Distance Du Grand Nuage De Magellan....Pages 78-85 The (log g , log T eff )-Diagram, a Fundamental HR-Diagram....Pages 86-89 Front Matter....Pages 91-91 Absolute Magnitude Determinations from Hydrogen-Line Photometry....Pages 93-113 A Preliminary Test of the Calibration of the Hβ System in Terms of Absolute Magnitudes and Intrinsic Colours for Early-Type Stars....Pages 114-116 Three-Dimensional Representation of A0-G5 Stars....Pages 117-119 The H γ -Absolute Magnitude Calibration....Pages 120-123 Calibration of MK Types by Fitting the HR Diagrams of Three Moving Clusters....Pages 124-125 Front Matter....Pages 91-91 Absolute Magnitudes of O Stars from A Study of Visual Multiple Systems....Pages 126-127 Front Matter....Pages 129-129 Ground Based and Extraterrestrial Observations of Stellar Flux....Pages 131-145 Line Blanketing in Real Stellar Atmospheres....Pages 146-148 Absolute Solar Intensities and the Solar Constant....Pages 149-152 Absolute Calibration of Stellar Temperatures....Pages 153-155 Comparison of Theoretical and Observed Indices for Three Photoelectric Photometric Systems....Pages 156-162 First Results of the Absolute Calibration of the u , v , b , y System of Filters....Pages 163-164 Radii and Fluxes of Long-Period Cepheids....Pages 165-170 Front Matter....Pages 171-171 The Use of Model Atmospheres for Temperature-Gravity Calibration....Pages 173-221 Ultraviolet Energy Distribution of He-Weak Stars....Pages 222-224 The Absolute Magnitude and Stellar Population of a Ba II Star....Pages 225-228 Front Matter....Pages 229-229 Stellar Temperature Scale and Bolometric Corrections....Pages 231-271 Front Matter....Pages 273-273 Remarks on the Photometric Criteria of Choice of the Standard Stars....Pages 275-297 Determination of the Apparent V Magnitudes....Pages 298-301 Distribution de L’energie Dans Le Spectre Ultraviolet de Quelques Étoiles....Pages 302-304