Imaging and location of fast neutron emissions by real-time time-of-flight

通过实时飞行时间对快中子发射进行成像和定位

基本信息

批准号：
EP/M02489X/1
负责人：
Malcolm Joyce
金额：
$ 67.65万
依托单位：
Lancaster University
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2015
资助国家：
英国
起止时间：
2015 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=EP%2FM02489X%2F1
关键词：
Imaging location fast neutron emissions

项目摘要

The proposed research comprises a study into a different way in which to use neutrons to characterise nuclear environments. The proposed project is a collaboration led by the Department of Engineering at Lancaster University with expertise from the Culham Centre for Fusion Energy. Neutrons make up approximately half of the subatomic particles that constitute the nuclei of matter around us. They are uncharged and therefore do not interact strongly with the environment in comparison with other common forms of radiation such as gamma rays, protons electrons etc. However, they are emitted as a result of nuclear reactions in reactors and particle accelerators and are thus present in many environments associated with truly global applications of nuclear technology such as nuclear power, propulsion, the prevention of nuclear proliferation and nuclear medicine. Fortunately, because fast neutrons do not travel at the speed of light in the same way that gamma rays do, they are readily separated from gamma rays on the basis of how long they take to travel a set distance. This approach is widely referred to as 'time-of-flight' (ToF).Exploiting the difference between the speed of fast neutrons and gamma rays on the basis of their time-of-flight is currently limited to rather esoteric applications such as finding the energy of neutrons at standards laboratories and particle accelerator facilities, for example at NPL and nTOF (CERN), respectively. Whilst this application is very important in the specific field of radiation metrology, wider application of the technique to infer the location of radioactive substances and the distribution of radiation emissions in industry and medicine has not yet been achieved. The focus of this proposal is to invert the widely-accepted ToF approach referred to above (by which the usual objective is to estimate the energy of neutrons) to see if we can locate and image the origin of fast neutrons in environments where they arise. The hypothesis at the focus of this proposal is that, based on our prior knowledge of the energy distribution of neutrons in typical environments of interest (such as power reactors and medical facilities), is to determine whether it is possible to obtain an estimate of the distance from the site of detection to the site of neutron emission. This information might then be used to locate and potentially image a neutron-emitting system or substance; an Engineering use of the time-of-flight method that has not been explored before. This research will thus determine whether time-of-flight, performed digitally and in real-time, can be used to indicate the location and to potentially image a source of neutron radiation. The key objective of this research is to determine whether the ToF approach can be applied as an Engineering capability that will have a range of potential applications in industry and medicine. These include for example: preventing the theft of nuclear materials (nuclear safeguards), nuclear reactor characterisation, nuclear security and the characterisation of neutron fields that result from the use of protons in cancer therapy.

拟议的研究包括一项研究，以一种使用中子来表征核环境的不同方式。拟议的项目是兰开斯特大学工程系领导的合作，并在库勒姆融合能源中心的专业知识中进行了专业知识。中子约占构成我们周围物质核的亚原子颗粒的一半。与其他常见的辐射（例如伽马射线，质子电子等）相比，它们与环境没有强烈的相互作用。但是，它们是由于反应堆和颗粒加速器中的核反应而发射的，因此在许多环境中存在于许多与核技术的真正全球应用相关的环境中，例如核能，核能，推进，预防核增殖和核医学和核药物的预防。幸运的是，由于快速中子不会像伽玛射线一样以光速行驶，因此它们很容易地与伽玛射线分开，因为他们花了多长时间行驶的距离。这种方法被广泛称为“飞行时间”（TOF）。探索快速中子和伽玛射线之间的差异目前仅限于飞行时间，仅限于相当深奥的应用，例如在NPL和NTOF（CERN）分别在NPL和NTOF（CERN上），诸如在标准实验室和颗粒机设施中找到中子的能量。尽管该应用在辐射计量的特定领域非常重要，但该技术在推断放射性物质的位置以及行业和医学中辐射排放的分布方面尚未实现。该提案的重点是颠倒上述广泛接受的TOF方法（通常的目的是估计中子的能量），以查看我们是否可以在其出现的环境中找到和图像快速中子的起源。该提议重点的假设是，基于我们对典型感兴趣环境中中子能量分布的先验知识（例如电反应堆和医疗设施），是确定是否可以获得从检测部位到中子排放部位的距离的估计。然后，这些信息可能被用来定位和可能对中子发射系统或物质进行图像；以前尚未探索的飞行时间方法的工程使用。因此，这项研究将确定飞行时间（以数字方式和实时执行）是否可用于指示位置并有可能形象形象中子辐射的来源。这项研究的主要目的是确定是否可以将TOF方法作为工程能力应用，该工程能力将在行业和医学中具有一系列潜在的应用。例如，其中包括：防止盗窃核材料（核压措施），核反应堆的表征，核安全以及由质子在癌症治疗中使用的中子场的表征。