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Title: Active remote detection of radioactivity based on electromagnetic signatures

This paper presents a new concept for the remote detection of radioactive materials. The concept is based on the detection of electromagnetic signatures in the vicinity of radioactive material and can enable stand-off detection at distances greater than 100 m. Radioactive materials emit gamma rays, which ionize the surrounding air. The ionized electrons rapidly attach to oxygen molecules forming O{sub 2}{sup −} ions. The density of O{sub 2}{sup −} around radioactive material can be several orders of magnitude greater than background levels. The elevated population of O{sub 2}{sup −} extends several meters around the radioactive material. Electrons are easily photo-detached from O{sub 2}{sup −} ions by laser radiation. The photo-detached electrons, in the presence of laser radiation, initiate avalanche ionization which results in a rapid increase in electron density. The rise in electron density induces a frequency modulation on a probe beam, which becomes a direct spectral signature for the presence of radioactive material.
Authors:
 [1] ;  [2] ;  [1] ; ;  [3] ;  [3] ;  [2] ;  [4]
  1. Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States)
  2. (United States)
  3. University of Maryland, College Park, Maryland 20742-4111 (United States)
  4. (Israel)
Publication Date:
OSTI Identifier:
22252164
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 21; Journal Issue: 1; Other Information: (c) 2014 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; AIR; BEAMS; DETECTION; DISTANCE; ELECTRON DENSITY; ELECTRONS; FREQUENCY MODULATION; GAMMA RADIATION; IONS; LASER RADIATION; MOLECULES; RADIOACTIVE MATERIALS; RADIOACTIVITY