Accession Number : ADA619753


Title :   A Characterization of the Ship-Effect in a Maritime Environment and Special Nuclear Material Detection


Descriptive Note : Trident Scholar Project rept. no. 441


Corporate Author : NAVAL ACADEMY ANNAPOLIS MD


Personal Author(s) : Rydalch, Fletcher D


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a619753.pdf


Report Date : 18 May 2015


Pagination or Media Count : 59


Abstract : Nuclear and radiological materials in the possession of those who intend to use them for malicious purposes are considered to be out of regulatory control. The ability to interdict the movement of special nuclear materials out of regulatory control is of utmost importance in national security. In the maritime environment where such material may be moved on large vessels, detection is complicated. Additionally, the level of the radiation background on and in the immediate vicinity of the ship (where an illicit source might be detected) is affected by the ship effect. The neutron and radiation ship effect is a phenomenon involving high energy physics where cosmic radiation interacts preferentially with high atomic number materials to produce additional background radiation. This research project's purpose was to advance the ability to identify special nuclear material aboard a maritime vessel by stand-off radiation detection through characterization of the ship effect. The objectives of this project were the completion of the following steps: (1) Integrating a portable and environmentally protected radiation detection system to be used in a mobile situation. (2) Conducting measurements of the background neutron radiation both on land and surrounding a ship on the water. (3) Simulating a radiation signature emitted from nuclear material aboard a ship using radiation transport software. (4) Comparing the measured radiation signatures and modeled source signatures to show the ship effect's impact on detection feasibility of nuclear material in a maritime environment.


Descriptors :   *ALPHA PARTICLE DETECTORS , *BACKGROUND RADIATION , *ELECTROMAGNETIC INTERFERENCE , *NEUTRON DETECTORS , *PORTABLE EQUIPMENT , *RADIOACTIVE MATERIALS , ATOMIC PROPERTIES , COSMIC RAYS , EXPERIMENTAL DESIGN , FALSE ALARMS , FEASIBILITY STUDIES , GERMANIUM , GLOBAL POSITIONING SYSTEM , HIGH ENERGY , MONTE CARLO METHOD , MULTISENSORS , NAVAL VESSELS , NUCLEAR RADIATION , OCEAN ENVIRONMENTS , RADIATION EFFECTS , RADIOACTIVE ISOTOPES , SCENARIOS , SOFTWARE TOOLS , SYSTEMS ENGINEERING , ULTRAVIOLET SIGNATURES , URANIUM


Subject Categories : Statistics and Probability
      Computer Programming and Software
      Nuclear Instrumentation
      Nuclear Physics & Elementary Particle Physics


Distribution Statement : APPROVED FOR PUBLIC RELEASE