Accelerating the development of novel technologies for nuclear physics

在核仪器领域，利用脉冲形状分析（PSA）进行伽马射线定位已被证明在推动核物理学在核结构和提高工业和医疗应用系统的跟踪和成像能力方面非常有用。随着核社区对这些跟踪探测器的需求增加，对高效PSA算法和精确模拟新型探测器几何形状的要求对于确保英国核物理社区保持在创新的前沿至关重要。该项目的重点是使用高性能计算系统来加速主要用于欧洲最先进的核谱仪之一AGATA阵列的技术开发。这些技术将处理大型数据集，以确定伽马射线在探测器内的相互作用位置，并以我们对AGATA探测器如何响应的理论理解为基础。从传统的基于CPU的算法到基于超并行GPU的算法的转变是一条有希望的研究途径。这些技术显示了GPU内核的巨大性能扩展，其中一些算法的运行速度比AGATA中使用的传统PSA技术快几个数量级（约450倍），同时提供相当的（有时是上级的）准确性。基于GPU的算法为像AGATA这样的大型项目提供了显著的优势，它们不仅能够满足在线PSA和跟踪的处理要求，而且还可以释放资源进行更复杂的分析。目前的资源已足以在简单情况下使用这些技术的原型，例如当伽马射线在AGATA探测器内仅相互作用一次时。然而，当伽马射线相互作用多次时，当伽马射线非常活跃时，识别这些相互作用发生的位置变得更具挑战性。该项目将使用高性能计算设备来加速基于GPU的算法的开发，这些算法可以在本地级别上分解多交互事件的复杂性。从长远来看，计算设备还可用于加速对英国核物理界重要的其他研究任务，例如运行模拟以设计用于核结构物理实验的新辐射传感器。

Within the field of Nuclear Instrumentation, the utilisation of Pulse Shape Analysis (PSA) for gamma-ray localisation has proven immensely useful in pushing the envelope of Nuclear Physics both in Nuclear Structure and by improving the tracking and imaging capabilities of systems for industrial and medical applications. As the demand from the nuclear community for these tracking detectors increases, the requirement for efficient PSA algorithms and accurate simulations of novel detector geometries is paramount to ensuring that the UK Nuclear Physics community remains at the forefront of innovation. This project focuses on using high performance computing systems to accelerate the development of techniques primarily for one of the state-of-the-art nuclear spectrometers in Europe, the AGATA array. The techniques will process large data sets to determine where the gamma rays interact within the detector, underpinned by a theoretical understanding of how we expect the AGATA detectors to respond.The move from conventional CPU-based algorithms to hyper-parallelised GPU-based algorithms is one avenue of research that shows promise. These techniques show great performance scaling with GPU cores with some algorithms capable of running several orders of magnitude faster (~450x) than conventional PSA techniques used in AGATA whilst providing comparable (and sometimes superior) accuracy. GPU-based algorithms provide a marked benefit for large-scale projects like AGATA, not only are they able to meet the processing requirements for online-PSA and tracking but they also free up resources for more complex analyses to be performed. Current resources have been sufficient to prototype the use of these techniques on simple cases, such as when a gamma-ray interact just once within an AGATA detector. However, when the gamma-ray interacts many times, as is likely when the gamma-ray is very energetic, it becomes much more challenging to identify where those interactions have taken place. This project will use high performance computing equipment to accelerate the development of GPU-based algorithms that can unpick the complexity of multiple-interaction events at a local level. In the long term, the computing equipment can also be used to accelerate other research tasks that are important to the UK nuclear physics community, such as running simulations to design new radiation sensors for use in nuclear structure physics experiments.