Spectroscopy of molecules relevant to astrophysics and the atmosphere

我们对天体-彗星、恒星、星云-以及恒星之间空间的分子组成的了解完全来自于这些环境中的分子发射的光，以及它们从背景源吸收的光。这项研究计划涉及在地球上的实验室研究这些分子，通过使用激光和光谱仪记录它们发射和吸收光的模式来非常详细地确定它们的物理性质。其中一些分子在化学上是稳定的，我们可以直接研究它们。另一些分子非常活跃，因此在陆地环境中产生后只能存活很短的时间(尽管它们可以在太空中存活很长时间，因为那里几乎没有可以反应的物质)。我们通过电子放电和专门准备的气体喷射来制造这些分子。由于它们只形成少量，我们必须设计出谨慎的方法来高灵敏度地探测它们。最近，一种新的设备已经可以用于这项研究。据萨斯卡通的加拿大光源公司报道，SK是一台同步加速器，能够产生从远红外到X射线的各种波长的非常强的光束。该设施的一条光束线专门用于远红外分子光谱。我们可以获得的光强度远远大于传统灯具所能提供的光强度，这将极大地提高我们测量的灵敏度。我们计划研究含有碳链、碳环、碱土金属和硅的分子，重点放在那些已经在天体物理源中探测到的分子，以及那些具有探测潜力的分子。这项研究将有助于澄清宇宙中物体的化学组成，并提供这些区域的物理和化学信息。

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.