Proposed Laboratory Simulation Studies of EUV-VUV Photolysis of Cosmic Icy Systems

拟定的宇宙冰系统 EUV-VUV 光解实验室模拟研究

• 批准号: 0604455
• 负责人: Chung-Yung Wu
• 金额: --
• 依托单位: University of Southern California
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-07-01 至 2010-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0604455&HistoricalAwards=false
• 关键词: Proposed; Laboratory; Simulation; Studies; EUV

AST 0604455WuWith this award, Dr. Wu and colleagues will carry out a photolysis study of astrophysical ice analogs. They will simultaneously investigate photon-induced chemical reactions and photon sputtering in a given ice system under the same experimental conditions in the same ultrahigh vacuum chamber. They will identify the type of molecules that form in the ice systems and that come off the ice surfaces, quantify their production yields, understand their production mechanisms, and ascertain their significance in astronomical environments. Recently, much progress has been made in the area of laboratory simulations of chemicalprocesses present in astronomical environments and in planetary systems. The body of this workincludes the study of photon irradiation and charged particle impact of ice grains and ices. Suchstudies are fundamental to the understanding of the evolution of the interstellar medium, and thechemical composition of primitive material in our solar system. Laboratory simulation has nowbecome a major tool in deciphering these complex phenomena which could have many otherimportant implications in astrophysics and astrobiology. Dr. Wu will continue his laboratory research efforts through measurements of in-situ Fourier Transform Infrared (FTIR) observations of the photolyzed samples of astronomic ice analogs. In addition, they will carry out simultaneous measurements of photon sputtering by utilizing a Quadrupole Mass Spectrometer (QMS). Chromatography techniques will be employed to analyze the photolyzed residues in addition to the in-situ studies. Much of the sophisticated equipment and advanced experimental techniques required for the proposed work have been developed by these researchers in previously funded projects and are available to this proposed project. A tunable intense synchrotron radiation light source available at the Synchrotron Radiation Research Center, Taiwan, will provide the required photons. The photon wavelengths selected to irradiate the icy samples will mainly correspond to the prominent solar helium, helium ion, and hydrogen lines. The ice systems to be investigated will include cosmic ice analogs containing H2O, CO, CO2, N2, NH3, CH4, CH3OH, SO2, and other relevant species. The results to be obtained are particularly relevant to our understanding of chemical and mass evolutions and synthesis in water-rich icy satellites of the giant planets, comets, the interstellar medium, molecular clouds, and protostellar regions.This project will train a graduate student, especially involving working with a synchrotronradiation facility. Dr. Wu has collaborated with scientists in the National Central University and the National Synchrotron Radiation Research Center in Taiwan in the past and will continue the collaborative efforts with this project. The research results will be used in teaching advanced courses for graduate and undergraduate students, and will be presented at scientific conferences. A better understanding of the photochemistry and photophysics of ices could also help us consider appropriate preventive measures in the event of the expanding ozone-hole that allows more ultraviolet radiation to penetrate to Earths troposphere.***

AST 0604455WUWITH这个奖项，Wu博士及其同事将对天体物理冰类似物进行光解研究。他们将在相同的超高真空室中相同的实验条件下同时研究光子诱导的化学反应和在给定冰系统中的光子溅射。他们将确定在冰系统中形成的分子的类型，并从冰面上脱落，量化其产量，了解其生产机制，并确定它们在天文环境中的重要性。最近，在天文环境和行星系统中存在的化学过程实验室模拟领域取得了很多进展。这种工作的身体包括对光子辐照的研究和冰晶粒和冰的带电颗粒的影响。这种研究是对星际介质进化的理解，以及我们太阳系中原始材料的三种组成的基础。实验室仿真已成为破译这些复杂现象的主要工具，该工具可能对天体物理学和天文学具有许多其他重要的影响。 Wu博士将通过测量天文冰类似物的光解样品的原位傅立叶变换红外（FTIR）观察来继续他的实验室研究工作。此外，他们将通过使用四极杆质谱仪（QMS）进行同时测量光子溅射。 除原位研究外，还将采用色谱技术来分析光解残基。这些研究人员在先前资助的项目中开发了拟议工作所需的许多复杂设备和先进的实验技术，并且可以使用该拟议项目。台湾同步加速器辐射研究中心可使用的可调激辐射辐射源将提供所需的光子。 选择用于照射冰冷样品的光子波长将主要对应于突出的太阳氦，氦离子和氢系。要研究的冰系统将包括包含H2O，CO，CO2，N2，NH3，CH4，CH4，CH3OH，SO2和其他相关物种的宇宙冰类似物。要获得的结果与我们对化学和质量进化的理解以及在水丰富的冰冷卫星，彗星，星际培养基，分子云和原生动物区域中的合成尤其重要。该项目将培训研究生，尤其涉及与同步介质设施一起工作。 Wu博士过去曾与国家中央大学的科学家和台湾的国家同步辐射研究中心合作，并将继续与该项目的合作努力。研究结果将用于教授研究生和本科生的高级课程，并将在科学会议上介绍。更好地了解ICE的光化学和光物理学也可以帮助我们考虑在扩展的臭氧孔时考虑适当的预防措施，从而使更多的紫外线辐射渗透到地球对流层上。*** ***