Wolf-Rayet Stars and Interrelations with Other Massive Stars in Galaxies: Proceedings of the 143rd Symposium of the International Astronomical Union,

ISBN-13: 9780792310860 / Angielski / Twarda / 1991 / 680 str.

International Astronomical Union; Karel A. Van Der Hucht; B. Hidayat

Opis

The first ideas for the symposium were generated in Brussels in the summer of 1986, dur- ing exquisite lunches in between HST proposal consortium meetings. At the time it was expected that soon after the previous IAU symposium (No. 116) devoted to luminous hot massive stars, a bonanza of new exciting observational material would become available, together with significant advances on the theoretical front. Also it was felt that Wolf- Rayet stars should feature predominantly, because that had not been the case since IAU Symposium No. 99 in 1981. Tradition requires that IAU symposia on hot massive stars take place in high lumi- nosity beach resorts, and after Buenos Aires, Qualicum Beach, Cozumel and Porto Heli, Bali sounded like a reasonable place. Therefore we were only too pleased with the invitation of the Indonesian astronomical community to host the symposium in Sanur (Denpasar). The aim of the symposium was to bring together both observers and theoreticians active in the field of Wolf-Rayet stars and related objects, to present and discuss their recent results, in order to expose to what extent consensus exists as to the physical and chemical properties of Wolf-Rayet stars, their evolutionary status and their interrelations with other massive stars in galaxies.

Spis treści

Welcoming Addresses.- Chairman Local Organizing Committee.- Chairman Scientific Organizing Committee.- Minister of Education and Culture.- Rector Institut Teknologi Bandung.- Director General of Higher Education.- After-Dinner Speech.- Wolf-Rayet stars in the Old Days.- Session I. Introduction.- A decade of Wolf-Rayet literature (Review).- Session II. Atmospheres.- Observations versus atmospheric models of WR stars (Review).- Evidence that WR stars are pre-main-sequence objects.- Theory of Wolf-Rayet atmospheres (Review).- Chemical composition in the envelopes of different WR subtypes.- Analyses of Wolf-Rayet spectra.- VLBI observations of WR stars.- Session II Poster Summaries.- Helium in Wolf-Rayet spectra.- Some emission lines in WCE stars have nearly constant line strengths.- The H/He ratio of WN stars.- Optical continuum formation in rotating-wind models of WR stars.- Identification and analysis of infrared lines of WC stars.- The hydrogen abundances in WN stars.- The properties of Population I WO stars.- X-rays from hot stars and the role of relativistic electrons.- Diffuse CIV emission around the WO star ST3.- More Einstein views of Wolf-Rayet stars.- The nitrogen spectra of WN stars: The WN6’ standard’ star HD192163 (WR136).- Session III. Intrinsic Variability.- Intrinsic variability of WR stars from an observational point of view (Review).- Sporadic variations in Wolf-Rayet stars.- (Intrinsic) variations of Wolf-Rayet stars.- Physical parameters of inhomogeneities in Wolf-Rayet winds.- Theory of intrinsic variability in hot-star winds (Review).- Theoretical results on WR instabilities.- Modelling the wind eclipses in WR+O binaries: The qualitative picture.- Session III Poster Summaries.- The UV variability of the WR star HD 50896 — A one day recurrence timescale.- EZ (easy?) Canis Majoris.- Emission line variations in ?2 Velorum.- The impact of polarimetry on Wolf-Rayet star models.- Gyroscopics as a means of demonstrating rotational instability in stars.- Session IV. Binaries.- Wolf-Rayet binaries: Observational aspects (Review).- New Wolf-Rayet binaries.- Massive contact binary systems.- WR binaries: theoretical aspects (Review).- Decoding of the light changes in Wolf-Rayet eclipsing binaries: an application to HD 5980 in the Small Magellanic Cloud.- IUE and massive binaries.- Session IV Poster Summaries.- Long period WR binaries.- The all-variable binary WR140.- The origin of WR140.- The structure of colliding stellar winds.- The light curve of V444 Cygni.- V444 Cygni and CQ Cephei, key Wolf-Rayet binary stars.- Spectroscopic CCD study of the two-day WN5+O8V binary CX.- Polarization variability of Wolf-Rayet binaries: constraints on WR parameters.- Spectroscopic CCD search for the unseen companions in three single-line WNL binaries.- UV observations of selective wind eclipses in the Wolf-Rayet star ? Velorum.- The Wolf-Rayet + of star binary AB7: A warmer in the Small Magellanic Cloud.- Emission line profiles in RY Scuti: a massive binary system in a pre-WR stage?.- Session V. Mass Loss.- Observations of Wolf-Rayet mass loss (Review).- IR observations of mass loss from massive stars.- Wolf-Rayet stellar wind theory (Review).- Deceleration zones in the winds of WR and P Cygni type stars.- Session V Poster Summaries.- Radio observations of massive OB stars.- Photometric determination of mass loss rates and orbital inclinations for WR binaries.- Terminal velocities for a large sample of O stars, supergiants, and Wolf-Rayet stars.- Stellar winds from massive stars: The influence of X-rays on the dynamics.- An analytical approach to the problem of mass loss from Wolf-Rayet stars.- Session VI. Enrichment.- Enrichment by Wolf-Rayet stars and other massive stars in gas, dust and energy (Review).- Dust formation in WC-star shells.- Cool supergiants in the solar neighborhood.- Ring nebulae around massive stars (Review).- Ring nebulae around of and WO stars.- G2. 4+1. 4: An extraordinary mass-loss bubble driven by an extreme WO star.- Abundances in WR nebulae.- The dynamics of the AG Car ring nebula.- Spectrophotometry of ring nebulae around Wolf-Rayet stars.- Massive stars and Giant HII regions: the high-energy picture (Review).- Warmers.- Session VI Poster Summaries.- Recurrent dust formation by Wolf-Rayet stars.- A two-component dust model for the WR ring nebula RCW 58.- On the chemodynamics of NGC 6888.- Detection of strong winds in giant extragalactic HII regions.- HI bubbles surrounding Wolf-Rayet stars.- A search for high excitation nebulae around Wolf-Rayet stars in the Magellanic Clouds.- Stellar content of the giant HII region NGC 604.- Session VII. Evolution.- Stellar Evolution in the upper HRD: Theory (Review).- Metallicity effects in massive star evolution and number frequencies of WR stars in galaxies.- Estimates of bolometric corrections for WR stars and progenitors of WN binaries.- Statistics of Wolf-Rayet binaries.- Observational aspects of stellar evolution in the upper HRD (Review).- LMC OB associations containing Wolf-Rayet stars.- The Wolf-Rayet connection — Luminous Blue Variables and evolved supergiants (Review).- AG Carinae and the WR phenomenon in Luminous Blue Variables.- New observations of LBV environments.- Nomenclature problems.- Explosions of helium stars and Type Ib/Icsupernovae (Review).- Are Wolf-Rayet stars the progenitors of Type Ib/Ic supernovae?.- X-ray and gamma-ray signatures of Wolf-Rayet supernova explosions.- Session VII Poster Summaries.- Is stellar wind mass loss during core hydrogen burning important for evolution?.- Single-lined spectroscopic appearances during the evolution of a massive binary system.- Convectively generated turbulent pressure: A possible cause for ? Car-type shell ejections.- Nucleosynthesis activity of WR stars: Implications for 26A1 in the Galaxy and isotopic anomalies in cosmic rays and the earlier solar system.- Is rotation a really important property to the understanding of the evolution of massive stars?.- New results in evolution in the upper HRD.- The WR / WR-progenitor number ratio: theory and observations.- The mass of WR progenitors.- The influence of WR like stellar wind mass loss rates on the evolution of massive core helium burning stars.- From LBV binary to WR+OB binary.- P Cygni: will it ever become a Wolf-Rayet star?.- The infrared spectrum of P Cygni.- A spectroscopic study of ? Car and the homunculus.- The distance to the S Dor type star HR Carinae.- R127 and its surrounding star cluster.- Photometric evidence of small’ s Dor type eruptions’ in S Dor type stars in or near minimum.- Observational evidence for evolutionary connections between Wolf-Rayet stars and red supergiants.- The anomalous A-type supergiants in the Magellanic Clouds — Evidence for post-red supergiant evolution.- Supernovae from Wolf-Rayet stars.- Progenitors of Type Ib supernovae.- Evolution of the progenitor of SN1987A in the HR diagram.- Session VIII. Inventory and Distribution.- Wolf-Rayet stars in nearby galaxies: Facts and fancies (Review).- Galactic Wolf-Rayet distribution and IMF.- A deep survey for faint galactic Wolf-Rayet stars.- Wolf-Rayet stars in Local Group Giant HII regions.- Wolf-Rayet populations in dwarf galaxies (Review).- Large number of Wolf-Rayet stars in emission line galaxies.- On the detection of WR stars in nearby galaxies.- Massive stars and galactic evolution (Review).- Session VIII Poster Summaries.- The distance to HD 50896 (EZ CMA).- Determination of the interstellar extinction toward WN stars from observed ubv color indices.- The distribution of M supergiants with large IR excess and WR stars in the Galaxy.- On the luminosity function of open clusters containing Wolf-Rayet stars.- The stellar association LH 99.- Multiplicity of very massive stars.- A WC9 star in the LMC.- Massive stars in M31 and M33 OB associations.- Optical spectroscopy of WR stars in M33 and M31.- H? emission-line stars in M33.- CCD survey for WR stars in the central part of M33.- A Wolf-Rayet Cluster in IC 4662.- Discovery of Wolf-Rayet stars in the SBmIII galaxy NGC 4214.- Wolf-Rayet galaxies.- Computer simulation of the evolution of active AGN: single supermassive star versus a cluster of massive WR stars.- Session IX. Summary.- Summary of symposium.- Closing Address.- Rector Universitas Udayana.- Object Index.