Pulsation and Mass Loss in Stars: Proceedings of a Workshop Held in Trieste, Italy, September 14–18, 1987

ISBN-13: 9789027727701 / Angielski / Twarda / 1988 / 336 str.

R. Stalio;L.A. Willson

Opis

Stellar mass loss is an essential part of the cycling of material from the interstellar medium into stars and back, and must be understood if we are to model processes on galactic to cosmological scales. The study of stellar winds and the effects of stellar mass loss has reached a particularly exciting stage where observational capabilities are increasingly able to provide interesting constraints on models and theories. Recent resu1ts from theoretical and observational work for both hot and cool stars with substantial winds have led to the suggestion that a combination of pulsation with other mechanisms makes for particularly efficient mass loss from stars. This provided the original motivation for the organization of this workshop. The conference was organized along relatively conventional lines according to the types of objects being scrutinized. However the true unity of the proceedings comes from the interplay of the mechanisms involved. For example, for the cool, luminous Mira variables, pulsation leads to shock waves that extend the atmosphere, enhancing dust formation; radiation pressure on dust drives the wind, cooling the atmosphere and in some cases suppressing the shocks. Similarly for the Be stars, both pulsation (in this case, non-radial) and radiation pressure (due to UV resonance lines) are expected to be important, and this expectation is at least qualitatively borne out by the observations.

Spis treści

I. Pulsation and Mass Loss from Cool Stars (M. Hack).- The Mechanism of Mass Loss from Pulsating Cool Stars.- The Fourier Decomposition Technique: Interpreting the Variations of Pulsating Stars.- The Winds from Cool Stars Including the Sun.- Summary of Selected Short Contributions on Cool Stars.- II. Pre-Main Sequence Objects (R. Stalio).- Circumstellar Matter and Winds in Young Stars.- Winds from Low Mass Protostars.- Evolution of the Outer Atmospheres of Pre-Main-Seguence Stars.- The FU Orionis Variables: Accretion and Mass Loss.- III. Helio- and Astro- Seismology (S. Jordan).- to Helio- and Astro- Seismology.- Observations of Solar Oscillations.- Solar and Stellar Nonradial Oscillations, Wave Propagation and Heating of the Upper Atmosphere.- Summary of Selected Contributions on the Sun.- IV. Pulsation and Mass Loss From Hot Stars (R. Polidan).- Mass Loss and Non-Radial Pulsations in Be Stars.- Time-Dependent Mass Loss from Hot Stars With and Without Radiative Driving.- Nonradial Pulsations and Early Be Stars: Angular Momentum Considerations.- Summary of Selected Contributions on Hot Stars.- V. Pulsation, Mass Loss, and Stellar Evolution (Y. Tuchman).- Pulsation and Mass Loss: Evolutionary Considerations.- Summary of the Workshop — remarks by J. M. Marlborough.- Author Index.- Object Index.