Scientists at the U.S. Naval Research Laboratory (NRL) are conducting research to improve the detection of weapons of mass destruction in maritime environments. In recognition of their efforts, they recently received a Best Paper Award at the 2013 IEEE Conference on Technologies for Homeland Security. The authors are Anthony Hutcheson, Bernard Phlips, Eric Wulf, Lee Mitchell, Neil Johnson, from NRL's Space Science Division, High Energy Space Environment Branch, and Byron Leas, SRA International, Inc.
Their paper, Maritime Detection of Radiological/Nuclear Threats with Hybrid Imaging System, won the Best Paper Award in the Land and Maritime Border Security Track at the IEEE conference. Five Best Paper Awards were presented—one for each track—Cyber Security; Biometrics and Forensics; Land and Maritime Border Security; Attack and Disaster Preparation, Recovery and Response, along with one overall best paper. The Best Papers will be published in Homeland Security Affairs, the peer-reviewed online journal of the Naval Postgraduate School Center for Homeland Defense and Security.
Scientists know that the remote detection of special nuclear materials is difficult because the materials are not very radioactive, the radiation signatures decrease rapidly with distance, and faint sources of radiation can be obscured by naturally occurring and man-made radioactive sources. The award-winning paper tells how the NRL team has developed the SuperMISTI stand-off detection system for maritime environments as part of the Office of Naval Research's (ONR's) Maritime Weapons of Mass Destruction Detection program. The instrument was deployed at Norfolk Naval Station in July 2012 as part of the ONR's Manta technology demonstration to determine the on-water performance of the system.
SuperMISTI is a hybrid detection, identification, and imaging system for sources of gamma-ray radiation at stand-off distances. NRL researchers designed and built SuperMISTI based on the Mobile Imaging and Spectroscopic Threat Identification (MISTI) system that they designed for the Department of Homeland Security Domestic Nuclear Detection Office Stand-Off Radiation Detection System program. The SuperMISTI system uses the high-resolution spectra of high-purity germanium (HPGe) detectors to detect and identify gamma-ray sources, as well as coded aperture technology and lower-cost sodium iodide (NaI) detectors to image and localize the detected sources. With its modular design, SuperMISTI allows the detection/identification and the imaging/localization portions to be used separately or together depending on the situation.
Dr. Hutcheson reports that NRL's SuperMISTI hybrid system has successfully detected, identified, and localized gamma and neutron sources in a maritime environment at operationally relevant distances. Since the completion of the Manta demonstration in 2012, NRL scientists have increased the number of HPGe detectors in the detection/identification subsystem from 24 to 48. This modification significantly enhances the gamma detection/identification capabilities of the system. The NRL team plans for further performance enhancements, including the use of a large-area BF3 detector array to increase neutron detection capabilities and the implementation of better localization algorithms for neutron sources.