Interferometric Spectroscopy.

Interferometers operating with high spectral resolution at visible and infrared wavelengths can provide information in spectral lines and velocity-resolved data on the milliarcsecond and sub-millisecond scale. This enables completely new observational approaches to many open problems regarding the physics of stars and circumstellar matter. Using fibers to couple the output from a relatively simple beam combiner to existing spectrographs offers a fast and cost-effective way to implement interferometric high-resolution spectroscopy. [ABSTRACT FROM AUTHOR]