ARI-MA: Electron Tracking for Advanced Gamma-Ray Imaging Applications in Homeland Security

该项目的目标是加强最近展示的基于电子跟踪的伽马辐射康普顿成像概念。这一概念有望提高核安全的检测、定位和表征能力，也适用于生物医学成像或天体物理学等其他领域。我们的方法是基于高分辨率的硅基电荷耦合器件（CCD）传感器，它提供了足够的分辨率，以确定通过康普顿散射过程散射的电子的初始方向。这使得能够在不使用灵敏度限制准直器的情况下逐个事件地重建入射伽马射线。Si和10 μ m的像素尺寸的组合使得能够实现足够的位置分辨率以确定入射方向和诱导康普顿散射过程的效率。该项目的具体目标是系统地评估和加强目前在硬件和软件方面的执行情况。已经开发了跟踪电子和执行图像重建的初步算法，可以通过考虑可以观察到的特征的更多细节以及通过将电子和伽马射线信息相关联来改进该算法。CCD方法的慢帧速率目前限制了事件到事件的重建。我们将实现CCD的条带读出，以实现电子径迹和相关伽马射线的事件到事件重建，并演示基于电子径迹的康普顿成像在真实的time.The项目的目标是演示辐射探测的新概念，使潜在的显着增加的能力，在检测，定位和表征核材料。极高分辨率硅传感器的最近和正在进行的发展可以用于测量相互作用过程的细节，这些过程可以用于获得更多的信息来重建伽马辐射。其应用领域可以设想为国土安全、核不扩散和国际保障、生物医学成像以及天体物理学和核物理学。该项目将为青年科学家提供出色的培训。

The goal of this project is to enhance the recently demonstrated concept of electron-tracking based Compton imaging of gamma radiation. This concept promises to increase the detection, localization, and characterization capabilities for nuclear security but also in other areas such as biomedical imaging or astrophysics. Our approach is based on high-resolution Si-based charge-coupled device (CCD) sensors which provides sufficient resolution to determine the initial direction of the electron that was scattered by means of the Compton scattering process. This enables the reconstruction of incident gamma rays on event-by-event basis without using a sensitivity-limiting collimator. The combination of Si and a pixel size of 10 um enables both sufficient position resolution to determine the incident direction and efficiency to induce the Compton scattering process. This project specifically aims at systematically evaluate and enhance the current implementation in terms of hardware and software. Preliminary algorithms to track the electron and to perform image reconstruction have been developed which can be improved by taking into account more details of the features that can be observed and by correlating the electron and gamma-ray information. The slow frame rate of the CCD approach is currently limiting the event-to-event reconstruction. We will implement the strip readout of the CCD to enable the event-to-event reconstruction of the electron track and the associated gamma ray and demonstrate electron-tracking-based Compton imaging in real time.The goal of this project is the demonstration of a new concept in radiation detection that enables potentially significant increased capabilities in the detection, localization, and characterization of nuclear materials. Recent and ongoing developments of very-high-resolution Si sensors can be used to measure details of interaction processes that can be used to gain more information to reconstruct gamma radiation. Applications can be envisioned in homeland security, nuclear non-proliferation and international safeguards, biomedical imaging as well as astrophysics and nuclear physics. The project will provide the excellent training of young scientists.