An Experimental Investigation of the Synthesis of Complex Organic Molecules in Interstellar Analog Ices

该项目研究复杂有机分子（COM）——包含碳、氢、氧和氮原子的有机分子——是如何在恒星之间的物质（“星际介质”，简称ISM）中形成的。该团队将利用实验室实验来研究COMs是如何在被冰覆盖的颗粒上形成的，就像那些预计存在于ISM中的颗粒一样。其中一些COMs可以作为“分子钟”，让我们揭开冷分子云和恒星形成区域的历史。PI和他的学生将通过实验确定星际分子的复杂程度。在这些实验室模拟中发现的任何COM都将成为未来在ISM中对这种分子进行天文搜索的候选分子。这个项目也可能使我们更接近于理解在多大程度上，关键类别的COMs可能是在ISM中制造的，并最终通过陨石传递给年轻的地球。PI和他的学生还将组织跨学科的“实验室天体物理学”研讨会，努力扩大夏威夷本地人对研究和教育活动的参与，并参与公共宣传活动。这些目标将通过系统地复制冷分子云中被冰覆盖的星际颗粒的条件，以及朝向高质量和低质量恒星形成区域的条件来实现。该团队将利用超高真空表面散射机将星际冰模拟样品暴露在各种模拟环境中，温度低至10 K，包括暴露于电离紫外线（莱曼- α）辐射。空间模拟室内无碎片真空紫外光电离新技术，以及几种互补的探测方案，将用于探测ISM条件下COMs的合成。

This project studies how complex organic molecules (COM) -- organic molecules containing atoms of carbon, hydrogen, oxygen, and nitrogen -- are formed in the material between the stars (the "interstellar medium", or ISM). The team will use laboratory experiments to study how COMs form on ice-coated grains like those expected to exist in the ISM. Some of these COMs might serve as 'molecular clocks' allowing us to unravel the history of cold molecular clouds and star forming regions. The PI and his students will experimentally determine just how complex we should expect interstellar molecules to become. Any COM discovered in these laboratory simulations will a candidate for future astronomical searches of this molecule in the ISM. This project might also bring us closer to understanding the extent to which key classes of COMs might have been manufactured in the ISM and eventually delivered to the young Earth via meteorites. The PI and his students will also organize interdisciplinary "laboratory astrophysics" workshops, work to broaden participation of native Hawai'ians in research and educational activities, and engage in public outreach activities. These goals will be achieved by systematically replicating the conditions of ice-coated interstellar grains within cold molecular clouds and toward high- and low-mass star forming regions. The team will utilize an ultra-high vacuum surface scattering machine to expose interstellar ice analog samples in various simulated environments, with temperatures as low as 10 K, and including exposure to ionizing ultraviolet (Lyman-alpha) radiation. The novel technology of fragment-free vacuum ultraviolet photoionization within a space simulation chamber, along with several complementary detection schemes, will be used to probe the synthesis of COMs in ISM conditions.