U.S. Government Capabilities to Support Analysis of Gamma Ray Data Submitted by Field Elements

As radiation detection in the interest of national security becomes increasingly commonplace, inevitable questions arise concerning the interpretation of data from handheld radioisotope identifiers (RIIDs). Field elements typically require fast answers to provide an effective defense and to minimize the impact on legitimate movement of people and goods. To support this need, on-call experts at Sandia, Los Alamos, and Lawrence Livermore national laboratories cooperate in resolving radiation alarms rapidly and accurately. We present an overview, describe the work in progress to improve capabilities, and report on some of the lessons learned. With the increasing use of radiation detection equipment to screen port-of-entry and other sites for illicit materials, the U.S. government has recognized the need to analyze complex gamma ray spectrum information and assess for potential threats. This is particularly important because the tools now available to first responders have limited capabilities in isotope identification. A formal mechanism to enable emergency response teams to request assistance was established in 2002, and has been continually evolved in response to operational experience. Scientists from Sandia, Los Alamos, and Lawrence Livermore national laboratories are on call 24 hours/day in a 7-day rotation. At least two different laboratories respond to each event to provide peer review. Specialists at the three nuclear weapons laboratories provide high-confidence answers when faced with questions affecting national security. A primary focus for the responders is accurate identification of threats. To this effect, analysts train with a variety of threat materials, nuclear weapons, and potential designs for improvised nuclear explosive devices (IND’s) and Radiation Dispersal Devices (RDD’s). Training includes both detailed spectrum analysis and hands-on training with nuclear materials and typical field team hardware. All of the analysts are active in research and development in various aspects of nuclear detection, and all are experts with many years of experience in gamma spectroscopy, handling of nuclear materials, and nuclear weapons. Analysts maintain currency in world radiological issues, advances in nuclear medicine, and potential threats through frequent updates and training.