Infrared specroscopy of free-flying dust particles

宇宙尘埃颗粒是年轻恒星系统中新行星的祖先，也是较老恒星系统中行星形成的后果。通过红外光谱对这些尘埃粒子的观测，可以描述行星系统的演化状态，并研究其中发生的动力学过程。今天，像斯皮策太空望远镜这样的新仪器提供了更多物体的数据，质量比以前更好。为了验证这些数据，需要对不同组成、形状和尺寸的颗粒进行实验室红外光谱测量。在本项目中，我们计划使用一种新的技术来测量这种实验室光谱的第一次自由飞行的粒子，调查的形状和大小的依赖性，并使他们通过公共数据库的观测结果进行比较。选定的观测光谱，特别是碎片盘的光谱，将与我们自己的新数据进行比较，以限制尘埃的组成，大小和形态。该项目的另一个重要目标是利用测得的谱带轮廓校准真实尘埃粒子集合的光散射模型。

Cosmic dust particles are progenitors of new planets in young stellar systems and an aftermath of planet formation in older ones. Observation of these dust particles by means of infrared Spectroscopy allows one to characterize the evolutionary state of planetary systems and to investigate the dynamical processes occuring in them. Today, new instruments such as the Spitzer space telescope deliver such data on more objects and in better quality than before. In order to interprete these data, laboratory measurements of infrared spectra of particles with different compositions, shapes and sizes are necessary. In the present project we plan to use a novel technique to measure such laboratory spectra for the first time on free-flying particles, to investigate the shape and size dependence, and to make them available for comparison with observations through a public data base. Selected observed spectra, especially such of debris disks, will be compared with the new data by ourselves in order to constrain the dust composition, size and morphology. Another important goal of this project is to use the measured band profiles for the calibration of light-scattering models for realistic dust particle ensembles.