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

该研究项目将研究在类似星际冰的冰模拟样品上含有碳、氢、氧和氮原子的复杂有机分子（COMs）的形成。为了研究这个问题，研究人员将在模拟星际空间环境的条件下，即超高真空、低温和暴露于紫外线辐射下，对冰模拟物进行实验室实验。这项研究的结果将使天文学家了解某些关键的COMs是如何在星际云中的冰上形成的，以及在太空中产生分子复杂性的过程。该项目将为研究生和本科生提供高级实验室天体物理学方面的培训，包括那些来自传统上在STEM领域代表性不足的群体的学生。该团队还将在当地高中举办科普讲座，使教育工作者能够将研究融入教学，并吸引学生从事STEM职业。研究小组将探索在星际冰类似物上合成关键类COMs——醛、酮、羧酸、酯和酰胺。他们将在低温、超高真空的空间模拟室中，将星际冰模拟样本暴露在莱曼α辐射下。实验中产生的分子将以高度互补的方式使用红外，拉曼，紫外-可见光谱以及质谱进行表征。这些测量将产生可靠的反应速率和分支分数，这是准确解释COMs天文观测所必需的。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This research project will investigate the formation of complex organic molecules (COMs) containing carbon, hydrogen, oxygen, and nitrogen atoms on ice analog samples resembling interstellar ices. To study this problem, the investigators will perform laboratory experiments on ice analogs at conditions mimicking the environment of interstellar space, viz. ultra-high vacuum, low temperatures, and exposure to ultraviolet radiation. Results from the study will allow astronomers to understand how certain key COMs are formed on ices within interstellar clouds and the processes that generate molecular complexity in space. This project will provide training in advanced laboratory astrophysics to graduate and undergraduate students, including ones from groups traditionally underrepresented in STEM. The team will also give popular science lectures at local high schools, enabling educators to incorporate research into teaching and attract students to pursue STEM careers.The research team will explore the synthesis of key classes of COMs – aldehydes, ketones, carboxylic acids, esters, and amides – on interstellar ice analogs. They will do so by exposing interstellar ice analog samples to Lyman alpha radiation in a low-temperature, ultra-high vacuum space simulation chamber. The molecules produced in the experiment will be characterized in a highly complementary manner using infrared, Raman, and ultraviolet-visible spectroscopy, as well as mass spectrometry. The measurements will yield reliable reaction rates and branching fractions necessary to accurately interpret astronomical observations of COMs.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.