Investigations into the structure of exotic atomic nuclei using stateof-the-art techniques of gamma-ray spectroscopy

多年来，对原子核行为的调查对许多行业至关重要，包括医药和核能。这项研究还使物理学家能够开发出有用的模型来解释和预测某些原子核的性质。然而，重要的是研究这些模型是否同样适用于质子和中子差异很大的核，通常称为奇异核。奇异核是这个项目的主要兴趣。当原子核处于激发态时，它们可以通过发射伽马射线来释放能量，这可以让物理学家深入了解这些外核子的性质。研究它们的许多有用方法之一是使用一种被称为伽马射线光谱学的技术。高纯度锗半导体探测器，如芝加哥阿贡国家实验室的大型伽马斯球探测器，可用于以高能量分辨率和高效率探测伽马射线。使用大型探测器阵列也意味着可以同时探测到许多伽马射线。这被称为伽马射线符合光谱学，这项技术也提供了有关这些原子核行为的有用信息。在这一研究领域遇到的困难之一是，外来原子核在反应中产生的可能性很小。将这些原子核与其他更多的原子核区分开来，需要一种称为通道选择的技术。这可以通过探测与伽马射线一致的蒸发粒子来实现。伽马射线可以揭示原子核的许多性质之一就是它的形状。在UWS感兴趣的外来核是八极形的，也就是众所周知的梨形。利用上述技术，UWS核物理小组计划研究被预测有八极形变的候选者，这个博士项目将涉及分析收集到的关于这些原子核的数据。

Over the years, the investigation into the behaviour of nuclei has been vital to many industries, includingmedicine and nuclear energy. This research has also allowed physicists to develop useful models that explainand predict the properties of some nuclei. However, it is important to investigate whether these models workas well for nuclei with a large difference in protons and neutrons, commonly known as exotic nuclei.Exotic nuclei are of primary interest in this project. When nuclei are in excited states they can releaseenergy by the emission of gamma rays, which can give physicists an insight into the properties of these exoticnuclei. One of the many useful ways in which they can be studied is using a technique known as gamma-rayspectroscopy. High purity germanium semiconductor detectors, such as the large array of detectors knownas Gammasphere at Argonne National Laboratory in Chicago, can be used to detect gamma rays with highenergy resolution and efficiency. Using large arrays of detectors also means that many gamma rays canbe detected simultaneously. This is known as gamma-ray coincidence spectroscopy and this technique alsoprovides useful information about the behaviour of these nuclei.One of the difficulties encountered in this area of research is that the exotic nuclei have a small probabilityof being produced in reactions. Identifying these nuclei from other more populated nuclei require a techniqueknown as channel selection. This can be done by detecting evaporated particles in coincidence with gammarays.One of the many properties that gamma rays can reveal about the nucleus is its shape. The exotic nucleiof interest at UWS are octupole deformed, otherwise known as pear shaped. Using the aforementionedtechniques, the UWS nuclear physics group plan to study candidates which are predicted to have octupoledeformation and this PhD project will involve analysing data gathered about these nuclei.