Mass loss and evolution of O-type stars : symposium no. 83 held at Vancouver Island, Canada, June 5-9, 1978

The organization of this Symposium had its beginnings at the International Astronomical Union General Assembly in Grenoble in 1976. The initial "rounding up" of the Scienti­ fic Organizing Committee was begun by Drs. Snow and Swings; most of us who became the eventual organizing committee met a few times during the Assembly and formulated the essential outlines of the meeting. Extensive correspondence with all the committee subsequently established the program. The idea was to bring together both observers and theoreticians to discuss the stellar winds and mass loss rates and their effects on evolutions of O-type stars. On the observational side, there are now spectroscopic data from the far UV to the near IR regions concerning the stellar winds. There is also information about the free-free emission in the wind from the IR and radio portions of the spectrum. Fortunately, these different detection methods give more or less the same mass loss rate for the one star, s Pup" which has been observed at all wavelengths. One of the intents of the first three sessions of this Symposium is to outline the eXisting data on mass loss rates as it per­ tains to the O-type stars. Front Matter....Pages i-xix Front Matter....Pages 1-1 The O Stars: Optical Review....Pages 3-22 H Alpha Variations in Two Mass Losing Stars....Pages 23-26 Short Term Variability of Line Strengths in Some of and WR Stars....Pages 27-30 Mass Loss Effects in the Spectrum of the O 6.5f Binary HD 153919....Pages 31-34 Mass Loss of B1Ia-O Supergiants and Evolutionary Consequences....Pages 35-38 On the Formation of Continuous Spectrum and Emission Line Profiles of P Cygni....Pages 39-42 Evidence for Non-Isotropic Mass Loss from Central Stars of Some Emission Nebulae....Pages 43-46 Mass Loss from Eta Carinae....Pages 47-50 Wolf-Rayet Stars in the Magellanic Clouds....Pages 51-54 Stellar Outflow: Relative Motions of Nebulae and of Stars....Pages 55-61 Front Matter....Pages 63-63 An Ultraviolet View of Stellar Winds....Pages 65-80 Modelling of UV Resonance Lines....Pages 81-92 O VI in Stellar Winds....Pages 93-94 C IV Resonance Line Profiles in O Stars....Pages 95-98 Winds in Hot, Subluminous Stars....Pages 99-102 Temperatures and Radii of O Stars....Pages 103-108 Analysis of UV Spectrophotometric Observations for O-type Stars....Pages 109-112 The Effective Temperatures of the O Stars....Pages 113-116 Front Matter....Pages 117-117 Radio and Infrared Emission by O-type and Related Stars....Pages 119-130 Near Infrared Spectra of O Stars and Related Objects....Pages 131-137 Front Matter....Pages 117-117 Infrared Observations of HDE 226868/CYG X-1 and HDE 245770/AO535+26....Pages 139-142 Infrared Excesses and Mass Loss: Implications for OB Stars in Carina and the LMC....Pages 143-146 Radio Emission from Flows....Pages 147-149 Radio Observations of Stellar Mass Loss....Pages 151-154 Radio Emission from Hot Stars at Two Centimeters....Pages 155-166 Front Matter....Pages 167-168 The Theory of Mass Loss from Hot Stars....Pages 169-173 Radiatively-Driven Winds: Model Improvements, Ionization Balance and the Infrared Spectrum....Pages 175-190 The Warm Wind Model....Pages 191-199 The Corona Plus Cool Wind Model for of Stars and OB Supergiants....Pages 201-213 The Thermodynamic Requirements on Atmospheric Models Imposed by Observed Stellar Nonthermal Mass-Fluxes and by Those Observed Nonthermal Features Enhanced in Xe Stars....Pages 215-234 Front Matter....Pages 235-235 The Domain of Radiatively Driven Mass Loss in the H-R Diagram....Pages 237-240 Stellar Corona Models....Pages 241-242 Synthetic Line Profiles in Early-Type Stellar Winds. I. H and He + ....Pages 243-247 The Hα Profile in Zeta Puppis....Pages 249-252 The Mass Loss Rate of γ Velorum....Pages 253-256 Wind Models for ζ Orionis....Pages 257-260 Binary Frequency among the O-type Stars....Pages 261-264 Contact Binaries of Spectral Type O....Pages 265-269 The O-type Spectroscopic Binary System HD 149404....Pages 271-275 The O-type Spectroscopic Binary System HD 93206....Pages 277-280 Front Matter....Pages 235-235 Mass Flow and Evolution of UW Canis Majoris....Pages 281-286 The Spectroscopic Binary γ 2 Velorum....Pages 287-289 The Binary Orbit of HD 92740....Pages 291-295 Results from the 1977 Coordinated Observing Campaign on HDE 226868 = Cygnus X-1....Pages 297-298 The Nature of the Runaways: Old Disk Population OB Stars?....Pages 299-299 The Distribution in Luminosity of OB Stars and Evolutionary Timescales....Pages 301-304 Hydrogen Deficiency and Mass Loss....Pages 305-310 Front Matter....Pages 311-311 Evolution of Single Stars with Mass Loss....Pages 313-336 Theoretical Evolution of Massive Stars with Mass Loss by Stellar Wind....Pages 337-348 Critical Rates of Stellar Mass Loss....Pages 349-356 Supergiant Mass Loss and the Cassiopeia a Progenitor....Pages 357-365 The Role of Rotation in the Evolution of Massive Stars Losing Mass....Pages 367-370 Evolution of a 30 M ⊙ Star with Mass Loss....Pages 371-374 Mass Conservation and Rapid Mass Loss on the Main Sequence....Pages 375-382 Front Matter....Pages 383-383 Evolution of Binary Stars with Mass Loss....Pages 385-399 Evolution of Massive Common Envelope Binaries and Mass Loss....Pages 401-407 The Influence of Stellar Wind Mass Loss on the Evolution of Massive Close Binaries.....Pages 409-414 Common Envelope Binaries and Mass Loss....Pages 415-420 HD 50896: An other WR Binary Star....Pages 421-427 Front Matter....Pages 429-429 Evolution of O Stars and the WR Connection....Pages 431-445 Front Matter....Pages 429-429 The Galactic WN7/WN8 Stars as Massive O Stars in Advanced Stages of Evolution....Pages 447-459 The Chemical Nature and Evolutionary Status of the Wolf-Rayet Stars....Pages 461-469 Of-WN Evolution: Spectral Types and Effective Temperatures....Pages 471-474 Observations of Velocity Fields in WN and Of Stars....Pages 475-478 BE 381: WN9 or 08 Iafpe?....Pages 479-482 Conservative and Non-Conservative Evolutionary Computations in Connection with Wolf-Rayet Binaries....Pages 483-490 Summary of the Conference — Projects for Future Research....Pages 491-498 Back Matter....Pages 499-501