The role and diversity of fullerenes in space

富勒烯在太空中的作用和多样性

• 批准号: RGPIN-2016-06047
• 负责人: Cami, Jan
• 金额: $ 1.97万
• 依托单位: University of Western Ontario
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=616071
• 关键词: role; diversity; fullerenes; space

The Universe contains a wide variety of carbonaceous molecules and dust grains that are first formed around red giant stars when they eject their outer envelopes into the interstellar medium. This carbonaceous material is further processed, first by intense UV radiation when the hot stellar core is exposed and lights up the surrounding material as a planetary nebula; later by energetic radiation and particles in the interstellar medium. Only the most stable species, such as buckyballs, can survive the rigors of space. Eventually, this material collects in the form of giant molecular clouds in which the next generation of stars and planets are formed - seeded thus with the molecules and dust ejected by red giant stars. Astronomers can study distant molecules and dust grains because each species imprints a specific color pattern (“spectral fingerprint”) in starlight. Recently, my research team discovered the unmistakable spectral fingerprint of buckyballs in observations of a planetary nebula. Buckyballs (also known as buckminsterfullerene or C60) are microscopic particles composed of 60 carbon atoms, shaped like a soccer ball. Very recently, it has been proven that charged buckyballs (C60+) are responsible for four of the “diffuse interstellar bands” (DIBs), a set of hundreds of mysterious spectral fingerprints that we see whenever starlight is dimmed by intervening clouds of interstellar gas and dust. This is the first - and only - time that any of these prominent interstellar fingerprints has been unambiguously identified with a specific molecule, demonstrating that buckyballs are ubiquitous and abundant in our galaxy. Although we have learned much about cosmic buckyballs in recent years, we do not yet understand how they form, what other related molecular structures form at the same time, or what other stable species is responsible for the rest of the DIBs. Answering those questions is essential for our understanding of the inventory of carbonaceous materials in the Universe - our cosmic roots. I propose a research program that will determine the precise conditions and chemical pathways that lead to the formation of buckyballs and other carbonaceous materials in space. I will do this by analyzing tailored, state-of-the-art astronomical observations, and by developing detailed astrochemical models for the formation of carbonaceous species in planetary nebulae. I will also produce the largest and most detailed DIB catalog ever, to find any DIBs that are related to C60, and to turn the DIBs into powerful probes of their environment. This research will reveal some of the hardiest carbonaceous materials in the Universe and elucidate the currently unknown pathways to form them. These processes are important to materials science researchers and the manufacturing industry. It will also turn several young researchers into data scientists with skills that are highly desired in Canadian industry.

宇宙包含了各种各样的碳质分子和尘埃颗粒，它们最初是在红巨星周围形成的，当它们将它们的外壳喷射到星际介质中时。这种碳质物质被进一步加工，首先是当热的恒星核心暴露出来时，强烈的紫外线辐射，照亮周围的物质，形成行星状星云;后来是高能辐射和星际介质中的粒子。只有最稳定的物种，如巴基球，才能在严酷的太空中生存下来。最终，这些物质以巨大分子云的形式聚集起来，在其中形成下一代恒星和行星-因此，红巨星喷出的分子和尘埃被播种。 天文学家可以研究遥远的分子和尘埃颗粒，因为每个物种在星光中都会留下特定的颜色图案（“光谱指纹”）。最近，我的研究小组在对一个行星状星云的观测中发现了巴基球的明确无误的光谱指纹。巴基球（也称为巴克敏斯特富勒烯或C60）是由60个碳原子组成的微观颗粒，形状像足球。最近，已经证明带电的巴基球（C60+）是四个“弥漫星际带”（DIB）的原因，这是一组数百个神秘的光谱指纹，每当星光被星际气体和尘埃的干预云变暗时，我们都会看到。这是第一次也是唯一一次，这些突出的星际指纹中的任何一个都被明确地确定为特定的分子，这表明巴基球在我们的银河系中无处不在，数量丰富。虽然近年来我们对宇宙巴基球有了很多了解，但我们还不知道它们是如何形成的，同时形成的其他相关分子结构，或者其他稳定的物种负责其余的DIB。回答这些问题对于我们理解宇宙中碳质物质的存量--我们的宇宙根源--至关重要。 我提出了一个研究计划，将确定精确的条件和化学途径，导致形成巴基球和其他碳质材料在太空中。我将通过分析量身定制的，最先进的天文观测，并通过开发行星状星云中碳物质形成的详细天体化学模型来实现这一目标。我还将制作有史以来最大和最详细的DIB目录，以找到与C60相关的任何DIB，并将DIB变成其环境的强大探测器。 这项研究将揭示宇宙中一些最坚硬的碳质材料，并阐明目前未知的形成它们的途径。这些过程对材料科学研究人员和制造业非常重要。它还将把几名年轻的研究人员培养成数据科学家，他们的技能是加拿大工业界非常需要的。