Binary and Multiple Stars As Tracers of Stellar Evolution: Proceedings of the 69th Colloquium of the International Astronomical Union, Held in Bamberg, F. R. G. , August 31 - September 3 1981

Front Matter....Pages i-xxx Front Matter....Pages 1-1 Evolution of Stars in the Post-Main Sequence Stage....Pages 3-18 Disk Instabilities in Hubble-Sandage Variables?....Pages 19-22 The Frequency of Cepheid Binaries....Pages 23-26 Search for Pulsating Stars in Multiple Stellar Systems....Pages 27-31 An AD HOC Hypothesis on the Pulsation of Delta Scuti Stars....Pages 33-35 On the Internal Structure of Main-Sequence Stars....Pages 37-46 A Study of the Orbital Periods of 22 Eclipsing Binaries....Pages 47-60 On the Group Formation of Stars in Stellar Associations....Pages 61-66 The Age of the Triple System HD 165590....Pages 67-71 Properties of Relativistic Linear Stellar Models....Pages 73-78 Front Matter....Pages 79-79 Evolutionary Trends in Wide Binaries....Pages 81-103 A Note About Multiple Systems of Dense Molecular Clouds....Pages 105-108 Trapezium Type Multiple Systems and Formation of Stars....Pages 109-113 A Hypothesis on the Richness of a Galaxy in Binary Stellar Systems....Pages 115-117 A Mass-Eccentricity Correlation in Spectroscopic and Visual Binary Orbits....Pages 119-122 Photometric Investigation of Visual Binaries with a Component above the Main Sequence....Pages 123-128 On the Distribution of Young Spectroscopic Binary Stars over the Major Semiaxes of their Orbits....Pages 129-131 Observational Selection in Spectroscopic Binary Eccentricities....Pages 133-143 Double Stars: The Closest and the Most Distant Systems....Pages 145-151 The Evolutionary State of Zeta Aurigae....Pages 153-156 Front Matter....Pages 157-157 Evolution of Close Binary Stars: Observational Aspects....Pages 159-181 Statistical Properties of Algol-Type Systems....Pages 183-186 Mass Loss in Algol-Type Stars: Implication on their Evolutionary Stage....Pages 187-189 Ultraviolet Light Curves of U Geminorum and VW Hydri....Pages 191-197 Statistical Models for Close Binaries....Pages 199-204 Structure and Evolution of SV Centauri....Pages 205-216 Age Determination in CW ERI = BV 1000....Pages 217-218 Numerical Calculations for Accretion Disks in Close Binary Systems....Pages 219-230 Quasi-Simultaneous Photometric and Polarimetric Observations of T Tau and RY Tau....Pages 231-238 S Cnc as a Case Study of Classical Algol Evolution....Pages 239-259 Structural Models for Beta Lyrae-Type Disks....Pages 261-273 Evolutionary Effects in Contact Binaries....Pages 275-278 Evolutionary Possibilities and Impossibilities for Solar Type Contact Binaries in NGC 188....Pages 279-287 Origin and Evolution of Contact Binaries of W UMa Type....Pages 289-299 Some Aspects of the Evolutionary Status of W Ursae Majoris Binaries Deduced from Observational Data....Pages 301-304 A Possible Explanation of Distortions in the Light Curves of VW Cep by Starspots....Pages 305-308 The IUE Observations of W UMa....Pages 309-315 Mass Flow due to Heating in a Binary System: Application to U Cephei....Pages 317-319 The Very Unusual Ultraviolet Spectra of R Arae....Pages 321-326 On a Possible Linkage between W-Type WUMa Systems and the Short Period RSCVn-Like Binaries....Pages 327-335 Front Matter....Pages 157-157 Recent Observational Evidence on W Ursae Majoris Stars....Pages 337-342 The Time Change of the AW UMa System....Pages 343-343 The Short-Period Non-Contact Binary Systems UU Lyn and GR Tau....Pages 345-349 On the Spatial Density of W UMa Type Stars....Pages 351-370 Front Matter....Pages 371-371 Binary Stars and SS433....Pages 373-388 Observations of Secular Changes in the Kinematic Model of SS433....Pages 389-397 Time Resolved Circular Polarimetry of White Dwarf Pulsars....Pages 399-401 The Mass Distribution of White Dwarfs and Central Stars of Planetary Nebulae....Pages 403-408 Abundance Peculiarities in White Dwarf Atmospheres as a Result of Binary Evolution?....Pages 409-411 The Minimum Orbital Period of Hydrogen-Rich Cataclysmic Binaries....Pages 413-414 Remarks on the Evolutionary Status of Cataclysmic Variables....Pages 415-415 Supernovae in Binary Systems: Production of Run-Away Stars and Pulsars....Pages 417-443 An Optical Burst in Sco X-1....Pages 445-445 The Formation of Massive White Dwarfs in Cataclysmic Binaries....Pages 447-451 UV Spectroscopy of the Novalike Variable TT Arietis....Pages 453-454 The Subdwarf Eclipsing Binary LB3459 (AA DOR)....Pages 455-456 Variability of Soft X-Ray Emission of Ex Hydrae Observed with Einstein Observatory....Pages 457-466 On the Possible Short-Period Irregular Light Fluctuations of V1357 Cyg = Cyg X-1....Pages 467-472 PU Vulpeculae (Object Honda-Kuwano 1979) — A Possible Short-Period Relative of the Symbiotic Stars....Pages 473-474 DID SU UMa Undergo a Classical Nova Outburst?....Pages 475-481 Front Matter....Pages 371-371 Does the Cataclysmic Binary Z Cha Contain a Black Dwarf Secondary?....Pages 483-488 Concluding Remarks....Pages 489-498 Back Matter....Pages 499-503 If Zdenek Kopal Department of Astronomy University of Manchester Your Magnificences, my Lord Mayor, ladies and gentlemen! It is a great pleasure for me to respond, on behalf of your foreign guests, to your gracious words of welcome; and to thank you for the wonderful reception which you nave extended to us. The city of Bamberg and its Remeis Sternwarte nas indeed been renowned allover the world for a great many years - as the place where your Observatory's first director, Professor Ernst Hartwig (1851-1923) - in addition to his other titles to fame - collaborated (with Gustav Muller of Potsdam) on the construc tion of the monumental Geschichte und Literatur des Lirhtwechsels der Veranderlichen Sterne, which since 1918 has (together with its sub sequent continuation) been a veritable vade-mecum of a1l students of variable stars; where the second director, Professor Ernst Zinner (1886-19]~ prepared his valuable Katalog der Verdachtigen Veranderlichen Sterne (192@ which safeguarded many an astronomer (including the present speaker in the days of his innocence) from premature discovery claims; and whose third director, Professor Wolfgang Strohmeier, initiated in 1959 the tradition of the international colloquia of which ours is the latest successor. It is indeed a great pleasure to welcome Professor Strohmeier - now Emeritus - among us; and to congratulate him on the grace with which he is carrying his years