Laboratory Studies of Astronomically Relevant Dust Species

赫克特博士和他在航空航天公司的同事们将提供与各种星际物质模型相关的小簇分子物种的新实验室数据。研究的主要物种是多环芳烃（PAH）单体和簇。直到20世纪80年代，星际和星周尘埃的模型都不需要包括小于50埃的单个颗粒。由于一系列出色的红外观测，这种情况发生了变化。这些测量揭示的辐射的起源，迄今为止只能通过假设大量的半径在3到50埃之间的星际物质来解释。实验室仪器也得到了发展，其中首次可以产生由各种材料形成的2到1000个原子的簇作为分子束。使用这种装置的实验表明，对于某些材料，特定大小的团簇异乎寻常地稳定。赫克特博士将使用结合最新技术进步的实验室仪器来产生和研究具有潜在天文学重要性的小粒子。

Dr. Hecht and his colleagues at the Aerospace Corporation will provide new laboratory data on small clusters of molecular species which are relevant to various models of interstellar material. The primary species to be studied are polycyclic aromatic hydrocarbon (PAH) monomers and clusters. Until the 1980s models for interstellar and circumstellar dust did not need to include individual grains smaller than 50 Angstroms. This changed due to a series of excellent observations in the infrared. These measurements revealed emission whose origin has only been explained to date by postulation of a significant amount of interstellar material with radii from 3 to 50 Angstroms. Laboratory instrumentation has also been developed where, for the first time, clusters of from 2 to 1000 atoms formed from a variety of materials can be produced as a molecular beam. Experiments using such an apparatus have shown that for some materials certain sized clusters are unusually stable. Dr. Hecht will use laboratory instrumentation that incorporates the latest in technological advances to produce and study small particles of potential astronomical importance.