Stellar Elemental Abundances Research Articles

An alternative explanation of the evolution of element abundance ratios during the history of the Galaxy

It is well established that stellar element abundances show a variation of some ratios, such as oxygen to iron and calcium to iron, with the overall metallicity of the star. This has been ascribed to a time-delay effect due to the different mean lifetimes of the stars and binaries that give rise to Type II and Type I supernovae. It is proposed that this identification may be premature, and that the observations could equally well be explained by a pseudo-secondary behaviour in the nucleosynthesis of iron

Infrared Spectroscopy of Stars

This paper reviews applications of IR techniques in stellar classification, studies of stellar photospheres, elemental and isotopic abundances, and the nature of remnant and ejected matter in near-circumstellar regions. Qualitative IR spectral classification of cool and hot stars is discussed, along with IR spectra of peculiar composite star systems and of obscured stars, and IR characteristics of stellar populations. The use of IR spectroscopy in theoretical modeling of stellar atmospheres is examined, IR indicators of stellar atmospheric composition are described, and contributions of IR spectroscopy to the study of stellar recycling of interstellar matter are summarized. The future of IR astronomy is also considered.