The Atmospheres of Early-Type Stars

The book gives a survey of recent research on atmospheres of early-type stars. Included are first results from the Hubble Space Telescope and ROSAT. The theoretical modelling of stellar atmospheres is also treated.

Inhalt
Galactic B-type Stars.- Non-LTE analyses of B stars.- Galactic B-type supergiants.- On the determination of effective temperature and surface gravity using Strömgren uvbyß photometry.- The mass and helium discrepancy in massive young stars.- A comparison between the orbital masses of early type binary components and masses predicted by stellar evolution.- B-type stars in young clusters.- Chemical abundances in early B-type stars.- The determination of accurate cosmic abundances from B-type stellar spectra.- The origin of distant B-type stars in the galactic halo.- Galactic abundance gradients from ob-type stars in young clusters and associations.- Ionizing radiation from early-type stars.- Abundance patterns in a stars: Carbon and silicon.- Quantitative analysis of A-type supergiants.- Abundances in rapidly rotating a stars.- Statistical equilibrium of Al I/II in a stars and the abundance of aluminium in Vega.- Analyses of B-type stars in the Magellanic Clouds.- The chemical composition of main sequence stars in the Magellanic Clouds.- GHRS observations of O Stars in other galaxies.- The winds of hot stars in M31 and M33.- Wolf-Rayet stars.- Spectrophotometry of Wolf-Rayet stars.- Near-Infrared Spectroscopy of Galactic Wolf-Rayet Stars.- Luminous Blue Variables.- Observed evolutionary changes in the visual magnitude of the luminous blue variable P Cygni.- Forbidden lines of [Fe II] and [N II] in P Cygni's envelope.- Spectroscopic observational data on P Cygni and comparison with the model of the bistable wind.- The spectroscopy of unusual high luminosity stars: HD 168607 and 6 Cas.- Discrete absorption components in O-type stars.- Analysis of circumstellar spectra of s dor.- Comoving frame calculations for ?-cephei.- Nonradial pulsations of O- and B-stars.- Analysisof line profile variations in pulsating B stars.- Mode identification of pulsating stars from line profile variations with the moment method.- Mode identification in beta Cephei stars from UV observations.- Magnetic fields in hot stars.- The structure of Ap star magnetic fields.- Diffusion, mass loss and accretion in stars.- Photospheric abundances in late-A and Am-Fm stars.- Effective temperature and models for early a stars: Application to 78Vir (A2P).- Silicon abundances in normal and mercury-manganese type late-B stars.- Radiative accelerations on Ga and Al ions in stable atmospheres of CP stars.- Si II autoionization lines in stratified atmosphere of Bp star.- He - variables.- Variable H? emission in the helium-strong star ? orionis C.- Lambda Bootis stars.- A spectroscopic abundance analysis of Lambda Bootis stars first results in LTE.- Hot subluminous stars.- The spectra of blue horizontal branch stars.- Weight watching in M 15.- Looking for gaps.- More on the progenitors of white dwarfs.- Non-LTE analysis of the Palomar Green subdwarf O stars.- A statistical complete sample of hot subdwarfs.- NLTE analysis of a SDO binary: HD128220.- NLTE analysis of helium rich subdwarf O stars.- Analysis of PG 1159 stars.- NLTE analysis of the hydrogen-deficient central star of the planetary nebula Abell 78.- Optical observations of the ultrahigh-excitation pre-white dwarf KPD 0005+5106.- The atmospheres of extreme helium stars.- Mass loss from ? Sgr and other helium stars.- Blue post-asymptotic giant branch stars at high galactic latitude.- Old planetary nuclei and their evolutionary connections.- Analysis of central stars of old planetary nebulae: Problems with the Balmer lines.- Hot white dwarfs.- ROSAT observations of white dwarfs.- Carbon enrichment in the outerlayers of hot helium-rich high gravity stars.- Prospective EUVE observations of hot white dwarfs.- Spectra of interacting binary white dwarf stars.- The opacity project A review.- The Lyman ? line wing and application for synthetic spectra of DA white dwarfs.- Ion-atom complexes and the absorption of radiation in stellar plasma.- Ion-atom complexes and the recombination in stellar plasma.- Stark broadening parameters for spectral lines of multicharged ions in stellar atmospheres: C IV, N V, O VI lines and regularities within an isoelectronic sequence.- On Stark line shifts in spectra of very hot stars.- Accelerated Lambda Iteration.- Instabilities in hot-star winds: Basic physics and recent developments.- Radiation-driven wind theory: Not (yet?) working.- Radiation-driven wind theory: The influence of turbulence.- Application of the etla approach in the comoving frame to the study of winds in hot stars.- Interactive LTE spectrum synthesis.- Calculations of line positions in the presence of magnetic and electric fields in white dwarf spectra.- Treatment Of strong magnetic fields in very hot stellar atmospheres.- Blends, frequency grids and the Scharmer scheme.- Multilevel non-LTE radiative transfer using exact complete and diagonal operators.- Iron line blanketing in NLTE model atmospheres for O stars: First results.- Calculations of non-LTE radiative transfer in extended outflowing atmospheres using the Sobolev approximation for line transfer.- 3d radiative line-transfer for disk-shaped be star envelopes.