ARI-MA: Advanced Concepts in Gamma-Ray Imaging for Homeland Security

University Of California-Berkeley, Berkeley CA

Investigators

Abstract

1039342 Vetter The objective of this proposal is to establish a program to develop and demonstrate enhanced detection and characterization schemes by using complementary information obtained from spectroscopic gamma-ray imaging instruments, visual sensors, and background measurements. By combining these modalities and data it is possible to significantly increase the sensitivity in detecting, identifying, and locating nuclear materials and to distinguish potential threat sources from legitimate and natural sources and associated temporal and spatial fluctuations. It enables the localization and mapping of radioactive sources onto objects in three dimensions. A new and important extension of this approach is based on the integration of background information that was obtained a priori. We propose to obtain extensive background data from recently demonstrated SORDS systems that will be made available and will allow us to develop improved detection algorithms. Intellectual Merit: Gamma-ray imaging is an established tool in biomedical applications, nuclear medicine, and astrophysics. However, recently the impact for homeland security applications was realized enabling a substantial increase in sensitivity over non-imaging systems by providing localization capabilities and the ability to distinguish a threat source from background and its associated spatial and temporal fluctuations. Systems are currently being tested consisting of large-area coded aperture gamma-ray imaging instruments and video cameras enabling the localization of potential threat objects. Our proposal goes beyond the state-of-the art in several ways: 1.) Enhance gamma-ray imaging capabilities by developing more advanced gamma-ray coding schemes and demonstrating them with detector arrays that are available at UC Berkeley. 2.) Measure and evaluate background data with one of the SORDS systems that are currently being demonstrated. The detailed measurement and characterization of backgrounds in locations that are relevant for homeland security is a very important component in improving the capability of detecting potential threat sources and distinguishing from background. 3.) Establish computermodeling tools and evaluate different imaging modalities and the integration of complementary information such as visual images and background. Such a framework will be closely coupled to ongoing efforts in developing advanced concepts in radiation detection. The proposed program draws upon unique expertise and capabilities provided at UC Berkeley and LBNL. It will complement currently ongoing efforts in Berkeley and will be closely aligned to existing programs including the exchange of students and scientists. The proposed program is an excellent vehicle for introducing students to modern research at universities and at closely located national laboratories. It will complement our framework for research and education in the area of advanced radiation detection by combining world-premier universities and national laboratories. Relation to Nuclear Threat Detection Advanced concepts in gamma-ray imaging in combination with other modalities provide the potential to significantly increase the sensitivity in the detection of nuclear materials, particularly in scenarios characterized by weak threat sources in the midst of stronger legitimate and natural background sources and associated temporal and spatial fluctuations, scenarios which are currently of particular concern for Homeland Security. The proposed work will enhance detection capabilities on land and sea as well as in air. Broader Impact Advanced gamma-ray detection and imaging concepts as proposed here will not only significantly improve the ability to detect and identify weak radioactive materials for Homeland Security but will also enhance capabilities in other national nuclear security related fields such as nuclear non-proliferation and abroad, e.g. for defense related nuclear detection. In addition, applications in basic research such as astrophysics will benefit from the improved imaging capabilities. In biomedical imaging, whether small-animal imaging for drug development or nuclear medicine to improve early cancer detection and cancer treatment will benefit from the proposed research.