Progress in Stellar Spectral Line Formation Theory

Spectral line formation theory is at the heart of astrophysical diagnostic. Our knowledge of abundances, in both stellar and interstellar contexts, comes almost enti­ rely from line analysis, as does a major fraction of our ability to model stellar atmospheres. As new facets of the universe become observable so the techniques of high resolution spectroscopy are brought to bear, with great reward. Improved instruments, such as echelle spectrographs, employ­ ing detectors of high quantum effi...