Spectroscopy of molecules relevant to astrophysics and the atmosphere

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Our knowledge of the molecular composition of astrophysical bodies - comets, stars, nebulae - and of the space between the stars comes exclusively from the light that molecules in these environment emit, and from the light that they absorb from background sources.  This research program involves the study of these molecules in laboratories on Earth to determine their physical properties in great detail by recording the patterns of their emission and absorption of light using lasers and spectrometers. Some of these molecules are chemically stable, and we can study them directly.  Others are very reactive, and therefore live only a short time once created in a terrestrial environment (although they can survive for a long time in space, since there is very little matter there with which to react).  We make these molecules via electrical discharges and in specially prepared jets of gas.  Since they form only in small quantitites, we have to devise careful means to probe them with high sensitivity.Recently, a new facility has become available for this research.  The Canadian Light Source in Saskatoon, SK is a synchrotron capable of producing very intense light beams at a wide range of wavelengths from the far-infrared to x-rays. One beam line at this facility is dedicated to far-infrared molecular spectroscopy.  The intensity of light we can obtain is far greater than conventional lamps can provide, which will greatly increase the sensitivity of our measurements.We plan to study molecules containing chains of carbon, rings of carbon, alkali-earth metals, and silicon, focusing on those molecules that have already been detected in astrophysical sources, and on those of high potential for detection.  The research will help to clarify the chemcial composition of objects in the universe, and to provide information on the physics and chemistry of these regions.