Analysis of gamma-ray nuclear resonant absorption (NRA) images for automatic explosives detection

1999 ◽  
Author(s):  
G. Feldman
Keyword(s):  
Gamma Ray ◽  
Resonant Absorption ◽  
Explosives Detection

scholarly journals Detectors for the gamma-ray resonant absorption (GRA) method of explosives detection in cargo: a comparative study

2004 ◽  
Author(s):  
David Vartsky ◽  
Mark B. Goldberg ◽  
Gideon Engler ◽  
Asher Shor ◽  
Aharon Goldschmidt ◽  
...  
Keyword(s):  
Comparative Study ◽  
Gamma Ray ◽  
Resonant Absorption ◽  
Explosives Detection

Gamma-ray nuclear resonance absorption (γ-NRA) for explosives detection in air cargo

1999 ◽  
Author(s):  
D. Vartsky ◽  
M. B. Goldberg ◽  
G. Engler ◽  
A. Goldschmidt ◽  
G. Feldman ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Resonance Absorption ◽  
Explosives Detection ◽  
Nuclear Resonance ◽  
Air Cargo

scholarly journals Gamma-ray imaging for explosives detection

2008 ◽  
Author(s):  
G. A. de Nolfo ◽  
S. D. Hunter ◽  
L. M. Barbier ◽  
J. T. Link ◽  
S. Son ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Explosives Detection ◽  
Gamma Ray Imaging

scholarly journals Physics of radio emission in gamma-ray pulsars

2016 ◽  
Vol 82 (2) ◽  
Author(s):  
S. A. Petrova
Keyword(s):  
Radio Emission ◽  
Gamma Ray ◽  
Radio Pulse ◽  
Position Angle ◽  
Resonant Absorption ◽  
Main Pulse ◽  
Wide Sense ◽  
Density Profiles ◽  
Millisecond Pulsars ◽  
Open Field Line

Propagation of radio emission in a pulsar magnetosphere is reviewed. The effects of polarization transfer, induced scattering and reprocessing to high energies are analysed with a special emphasis on the implications for the gamma-ray pulsars. The possibilities of the pulsar plasma diagnostics based on the observed radio pulse characteristics are also outlined. As an example, the plasma number density profiles obtained from the polarization data for the Vela and the gamma-ray millisecond pulsars J1446-4701, J1939+2134 and J1744-1134 are presented. The number densities derived tend to be the highest/lowest when the radio pulse leads/lags the gamma-ray peak. In the PSR J1939+2134, the plasma density profiles for the main pulse and interpulse appear to fit exactly the same curve, testifying to the origin of both radio components above the same magnetic pole and their propagation through the same plasma flow in opposite directions. The millisecond radio pulse components exhibiting flat position angle curves are suggested to result from the induced scattering of the main pulse by the same particles that generate gamma rays. This is believed to underlie the wide-sense radio/gamma-ray correlation in the millisecond pulsars. The radio quietness of young gamma-ray pulsars is attributed to resonant absorption, whereas the radio loudness to the radio beam escape through the periphery of the open field line tube.

scholarly journals Resonant absorption troughs in the gamma-ray spectra of QSO

2005 ◽  
Vol 436 (3) ◽  
pp. 763-784 ◽  
Author(s):  
A. F. Iyudin ◽  
O. Reimer ◽  
V. Burwitz ◽  
J. Greiner ◽  
A. Reimer
Keyword(s):  
Gamma Ray ◽  
Resonant Absorption

ULTIMATE LEVELS OF EXPLOSIVES DETECTION VIA TAGGED NEUTRONS

2014 ◽  
Vol 27 ◽  
pp. 1460131 ◽  
Author(s):  
V. F. BATYAEV ◽  
S. G. BELICHENKO ◽  
R. R. BESTAEV ◽  
A. V. GAVRYUCHENKOV
Keyword(s):  
Neutron Generator ◽  
Gamma Ray ◽  
Irradiation Time ◽  
Geometrical Model ◽  
Explosives Detection ◽  
Operating Characteristics ◽  
Computational Simulations ◽  
Neutron Physics ◽  
Detection And Identification ◽  
Gamma Ray Detector

Capabilities of the Tagged Neutron (TN) method for detection and identification of explosives materials (EM) are explored using an idealized geometrical model that includes a 14 MeV neutron generator with an integrated alpha detector, a gamma-ray detector based on BGO/LYSO crystals, and irradiated samples in the form of simulated EM (TNT, tetryl, RDX, etc.) or benign material (BM) such as cotton, paper, etc. Research was carried out under the framework of computational simulations of neutron physics processes by Monte Carlo methods as well as experimental measurements using an ING-27 neutron generator produced by VNIIA. The work resulted in a comparison between measured and simulated ROC (receiver operating characteristics) curves obtained via integration of analytically expressed functions of irradiation time, mass, and type of EM and BM. Experimental results indicate that 0.3 kg of tetryl simulant located 45 cm from the neutron generator is detected in 97% of cases after a one minute measurement, with the false-alarm rate being highly dependent on the type of BM present: from ∼0% in the case of water to ∼5% in the case of silk. Comparison of simulated and experimental data for these results shows they are in agreement in cases where the simulations account for neutron scattering from the object and background effects.

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