Experimental and Theoretical Studies of Light Scattering from Irregularly Shaped Particles

本项目的目标是对不规则形状粒子的光散射进行完整、全面和定量的描述。同时多角度，校准散射矩阵测量设备，基本上所有角度从0.1度到180度将被设计和建造。该装置的一个重要特点是，在以前对不规则形状粒子的研究中没有发现，它能够达到非常小的角度，这是检测吉尼尔和瑞利散射所必需的。利用该装置，将研究各种不规则颗粒的散射，包括煤烟聚集体、湿化煤烟聚集体和干燥煤烟聚集体、矿物粉尘和湿化粉尘以及具有几何形状的结晶固体。这些粒子对大气气溶胶和全球环境具有重要意义。实验和理论工作的结合将对所有类型粒子的散射产生定量而又物理的描述。这种描述在全球气候模型中实现起来既准确又直接。智力优势：本研究将在实验数据和系统理论计算中广泛应用和检验q空间分析方法。该方法是一种全新的光散射分析方法，具有广泛的应用前景。从这个q空间的角度来看，系统的研究应该会产生一个新的散射的物理图像，这将给散射是如何工作的一个前所未有的智力直觉。更广泛的影响：当今人类面临的最重大问题之一是全球气候变化。这项研究的结果将直接关系到气溶胶如何影响我们的全球环境的问题。这项研究的目标是理解和准确描述任何一种粒子的光散射，包括大气中出现的各种非球形粒子。有了这些知识，就可以预测气溶胶对环境的直接影响，并可以准确地检测和测量大气中的气溶胶含量。有许多关于教育，推广和课程开发的项目将直接产生或与这项工作密切相关，包括：青少年女性夏季研讨会，本科生参与研究，关于光散射的高级本科课程，在高中演讲，研究生指导，以及撰写关于光散射的专著。

The goal of this project is to develop a complete, comprehensive and quantitative description of light scattering by irregularly shaped particles. A device for simultaneous multi-angle, calibrated scattering matrix measurements over essentially all angles from 0.1 degrees to 180 degrees will be designed and built. An important characteristic of the device, not found in previous studies of irregularly shaped particles, is the ability to go to very small angles necessary to detect the Guinier and Rayleigh scattering regimes. With this device, scattering by a wide variety of irregular particles including soot aggregates, humidified soot aggregates and then dried soot aggregates, mineral dusts and humidified dusts, and crystalline solids with geometric shapes will be studied. Such particles are of significance for atmospheric aerosols and the global environment. The combined experimental and theoretical work will yield a quantitative yet physical description of scattering by all types of particles. This description will be both accurate and straightforward to implement into global climate models.Intellectual Merit: The study will apply and test broadly the q-space analysis method to both the experimental data and systematic theoretical calculations. The method is a completely new way of analyzing light scattering that past work indicates will be broadly applicable. With this q-space perspective, the systematic studies should yield a new physical picture of scattering that will give an unprecedented intellectual intuition on how scattering works.Broader Impacts: One of the most significant problems facing humanity today is global climate change. The results of this research will have direct bearing on the problem of how aerosols affect our global environment. The goal of this study is to understand and accurately describe light scattering from any kind of particle including the wide variety of non-spherical shapes that occur in the atmosphere. With such knowledge, the direct impact of aerosols on the environment can be predicted and the aerosol content in the atmosphere can be accurately detected and measured.There are a number of projects regarding education, outreach and curriculum development that will directly result from or be significantly related to this work including: a summer workshop for teen women, involvement of undergraduates in research, an upper level undergraduate course on light scattering, talks at high schools, mentorship of graduate students, and writing of a monograph on light scattering.