From atoms to prebiotic molecules on the surface of cosmic dust grains

重新提交的研究项目将处理重要有机分子的形成，以及可以作为形成地球或系外行星上更复杂的生物构建块的前体材料的益生元分子。在星际介质和原行星盘中产生的益生元分子，以及它们最终被彗星和陨石运送和积累到行星上，代表了复杂有机物在天体化学过程中进化的一个有趣场景。氨基酸和糖分子可以被认为是重要的生物相关分子，因为它们分别是蛋白质和核苷的组成部分。氨基酸和糖分子的前体已经在不同的天体物理环境中被发现。甘氨酸是最简单的氨基酸，已经在彗星和陨石中检测到。本研究计划致力于在ISM中普遍存在的条件下，对宇宙颗粒类似物（包括碳质和硅质尘埃颗粒）表面复杂有机分子的形成进行系统的实验研究。一系列的实验将集中于耐火碳表面与由H和O、N和H以及N和O原子组成的原子束的相互作用。通过碳颗粒的贡献和侵蚀，将研究益生元分子的形成，包括重要的含氢、含氧和含氮分子。研究项目的第二部分将致力于CO和HCN在硅酸盐和碳颗粒表面的加氢反应。该项目的主要目标集中在更好地理解颗粒和分子的天体化学演化，以及研究ISM探测到的COMs的天体化学起源。此外，我们希望研究有利于在尘埃颗粒上形成氨基酸或糖分子前体等益生元分子的环境条件。该结果将为在星际介质的不同区域合成生物分子提供重要信息。

The re-submitted research project will deal with the formation of important organic as well as prebiotic molecules that could serve as precursor materials for the formation of more complex biological building blocks of life on Earth or exoplanets. The generation of prebiotic molecules in the interstellar medium and protoplanetary disks and their final delivery and accumulation to planets by comets and meteorites represents an interesting scenario for the evolution of complex organics by astrochemical processes. Amino acids and sugar molecules can be considered as important biological-relevant molecules, because they are the building blocks of proteins and nucleosides, respectively. Precursors of amino acids and sugar molecules have been identified in different astrophysical environments. Glycine, the simplest amino acid, has been detected in comets and meteorites. This research proposal is devoted to systematic experimental studies on the formation of complex organic molecules on the surface of cosmic grain analogs including carbonaceous and siliceous dust grains at conditions prevailing in the ISM. A series of experiments will focus on the interaction of refractory carbon surfaces with atomic beams consisting of H and O, N and H, as well as N and O atoms. The formation of prebiotic molecules including important hydrogen- oxygen- and nitrogen-bearing molecules by the contribution and erosion of carbon grains will be studied. The second part of the research project will be dedicated to the hydrogenation reactions of CO and HCN on the surface of silicates and carbon particles. The main goals of the project concentrate on a better understanding of the astrochemical evolution of grains and molecules and the study of the astrochemical origins of COMs detected in the ISM. In addition, we want to investigate the environmental conditions that favor the formation of prebiotic molecules such as amino acids or precursors of sugar molecules on dust grains. The results will provide important information on the synthesis of biomolecules in different areas of the interstellar medium.