Nuclear Physics in the Cosmos

自人类诞生以来，人类一直对星星着迷，但直到上个世纪，我们才真正开始理解它们在回答我们最深刻的问题上的意义，“我们从哪里来？”在20世纪20年代早期，有人提出核反应产生了使恒星发光的能量。这些相同的核反应后来被发现是几乎所有化学元素产生的原因。当恒星走到生命周期的尽头，它们的燃料最终耗尽时，它们可以通过恒星爆发和灾难性爆炸将部分或全部物质喷射到宇宙中。这些物质为新恒星、行星和生命本身的诞生提供了基石。我们的太阳和它的行星就是由这些从恒星祖先的碎片中收集的物质创造出来的。因此，地球上的每一种生物都可以被看作是由星尘构成的。天文学和陨石内含物分析的最新进展为天体物理现象提供了前所未有的观测数据，这些天体物理现象以其喷射或流出丰富了宇宙。特别是，在陨石中发现的前太阳颗粒（pre-solar grains），即微小的物质碎片，揭示了在太阳系形成之前发生的灾难性事件（如超新星）中产生的丰富化学元素的信息。相比之下，现代太空望远镜为我们银河系中正在发生的恒星过程的特性提供了新的见解。观测天文学的这两次巨大飞跃极大地拓宽了我们对恒星环境的认识。然而，令人惊讶的是，由于驱动恒星爆发的潜在核反应过程的不确定性，恒星核合成的许多关键阶段仍未完全了解。我的研究重点是通过研究天体物理环境中涉及的核反应来解决这些问题，最终目标是在理论模型和天文观测之间进行有意义的比较。应当指出，对实验人员来说，研究发生在恒星内部的核反应是出了名的困难。这是由于在地球实验室中重现恒星现象的极端条件是一项艰巨的任务。然而，通过使用创新的实验技术，有可能绕过这个问题，间接地研究感兴趣的核反应。这些间接调查占了我研究计划的大部分。在每一项研究中，获得了天体物理过程的不稳定最终产物的关键核物理信息，并用于确定核反应发生的速率。这些速率控制着恒星环境中核合成的能量产生和路径，因此对正在研究的天体物理现象的观测特性有很强的影响。这是一个非常令人兴奋的物理研究领域，提供了核结构和反应领域与天文学和天体物理学之间的相互联系。

Since the dawn of mankind the human race has had a fascination with the stars but it's only in the last century that we have truly begun to understand their significance in answering our deepest of questions, "where do we come from?" In the early 1920s, it was suggested that nuclear reactions generate the energy that makes stars shine. These same nuclear reactions were then later discovered to be responsible for the creation of almost all of the chemical elements. When stars come to the end of their life cycles, their fuel finally spent, they can eject part or all of their matter into the Universe via stellar outbursts and cataclysmic explosions. This material provides the building blocks for the birth of new stars, of planets and of life itself. Our own Sun and its complement of planets were created from such material gathered from the debris of stellar ancestors. Thus, every living creature on Earth can be viewed as literally being made of stardust.Recent advances in astronomy and in the analysis of meteoritic inclusions have provided unprecedented observational data on astrophysical phenomena that enrich the Universe with their ejecta or outflow. In particular, pre-solar grains, tiny pieces of material found in meteorites, are revealing a wealth of information on the abundance of chemical elements produced in cataclysmic events, such as Supernovae, that occurred prior to the formation of the Solar System. In contrast, modern space-based telescopes provide a fresh insight into the properties of ongoing stellar processes occurring in our Galaxy. These two massive leaps in observational astronomy have broadened our knowledge of stellar environments tremendously. However, quite astonishingly, many key stages of stellar nucleosynthesis are still not fully understood, owing to uncertainties in the underlying nuclear reaction processes that drive the stellar outbursts. My research focuses on resolving these issues, by investigating the nuclear reactions involved in astrophysical environments, with the ultimate goal of allowing a meaningful comparison to be made between theoretical models and astronomical observations. It should be noted that the study of nuclear reactions that occur in stellar interiors is notoriously difficult for the experimenter. This is due to the formidable task of recreating the extreme conditions of stellar phenomena in a terrestrial laboratory. However, by using innovative experimental techniques, it is possible to bypass this problem and investigate the nuclear reactions of interest indirectly. These indirect investigations represent the bulk of my research programme. In each study, key nuclear physics information is obtained on the unstable end products of an astrophysical process and used to determine the rate at which the nuclear reaction takes place. These rates govern both the energy generation and path of nucleosynthesis in stellar environments and as such, have a strong influence on the observational properties of the astrophysical phenomena under investigation. This is an extremely exciting area of physics research, providing an interlinking between the fields of nuclear structure and reactions and astronomy and astrophysics.