Project P5: Dust opacity measurements for debris disks

碎片盘中的尘埃颗粒很可能具有复杂的成分和结构，这应该决定了它们在远红外和（亚）毫米波长上的发射率，这是它们主要被观察到的。因此，要对这些波长的观测数据进行安全的解释，就需要对各种光学材料的特性和这种复杂粒子结构的光学特性有深刻的了解。在这个项目中，我们的目标是在相关波长和温度范围内确定（可能的）粉尘成分材料的光学数据，并测量复杂粉尘混合物的不透明度，作为光学模型的基准结果。在基础物理方面，第一个问题将主要解决温度和结构缺陷对单个材料吸收指数的影响，而第二个问题我们将研究孔隙率和强吸收外加剂对有效吸收截面的影响。我们将与P6、P7和P8项目密切合作，选择和生产样品，同时将多孔和非均匀团聚体的不透明度测量数据与P4的模拟进行比较，并将测量的光学常数用于这些模拟。

Dust particles in debris disks have, most likely, a complex composition and structure, which should determine their emissivity at the far-infrared and (sub-)millimeter wavelengths, at which they are primarily observed. A safe interpretation of observational data at these wavelengths thus requires a profound knowledge of various optical material properties and of the optics of such complex particle structures. With this project we aim at determining optical data for (possible) dust constituent materials in the relevant wavelength and temperature range, and at measuring the opacity of complex dust mixtures as benchmark results for optical models. In terms of underlying physics, the first issue will address mainly the influence of temperature and of structural defects on absorption indices of individual materials, while with the second we will investigate the influence of porosity and of strongly absorbing admixtures on the effective absorption cross section. We will closely collaborate with projects P6, P7, and P8 for the choice and production of samples, while measured opacity data of porous and inhomogeneous agglomerates will be compared with the simulations performed in P4, and measured optical constants will be used in those simulations.