SBIR-STTR Award

Our research proposal of land mines detection by a nuclear activation method is based on a new extremely intense, compact pulsed source of 14.1 mev neutrons (with a yield y(n)=5.10(12) neutrons/50 ns pulse and a source repetition rate 1 hz). We have developed and carried out experiments witii (a) compact accelerator plasma target systems (cast). This is a new generation of devices which is obtained by improving plasma focus machines of the mather type. (b) powerful 3d-monte carlo (for treating random walk of radiation through matter; analogue, continuous in energy and space, numerical code which is suitable for handling any geometry, materials, nuclear processes). For phase I we propose to generate-numerically-energy spectra of neutrons and gamms (including their time of emission) from neutronirradiated mines (we consider buried mines in the ground; the spectra will be determined at the location of the detector surface). This will establish the optimum ranges (energy, time) of the detection method, the characteristic parameters of the neutron source, the required radiation shields for personnel protection. In phase ii we propose (a) to convert the capt source (used in laboratory experiments) into a prototype for field operation testing; (b) to provide a proof-of-principle for the operation of the choosen detection system from phase I.

We have documented in Phase I the feasibility of a new, relible, nuclear method for detecting mines buried in the ground. The method is based on the detection of the radiation response from illuminating a hidden mine with 14.7 MeV neutrons. The detection is focused on the identifiction of the H and N __-ray fingerprint from (n,__) reactions of slowed-down (not thermal) neutrons and on the identification of Cand O-backscattered-neutron fingerprints in the energy intervals 6.5 MeV < En < 11 MeV and En > 11 MeV. One basic condition for the applicability of this mine-hunting method is the use of a pulsed neutron generator with a neutron yield 10(10) - 10(13) neutrons/pulse, and pulse-duration ~ 50 ns. These requirements are easily satisifed at the present time with one of our CAPT generators. This type of generator, a compact-accelerator/plasma-target system, or CAPT, is the result of major improvements obtained in our laboratory of an earlier version of magnetized-plasma-target generator (plasma focus type). A vital and most urgent R&D objective for practical hunting-method operation in the field is the development of a new type of fast neutron detector with selective efficiency of neutron detection, i.e., with appreciable efficiency limited to a selected energy interval. Design, production, calibration and experimental verification of the capability of this detector is the main task of the Phase II proposed effort. Anticipated Benefits/Potential Commercial Applications - Substantial benefits are anticipated from the development of the present detector system for a variety of applications as explosive detection in airports, fast-neutron radiography of thick objects with high-resolution in time and space. The neutron generator CAPT, with suitable filling of the discharge chamber, can also be used as x-ray source for high resolution lithography and as generator of short-life isotopes for medical applications. Commercial applications of detector and CAPT source are expected from the R&D.

Keywords:
Mine Detectors Land Mines High Explosives Neutron Sources Radiation Shiel Super Intense Mines Hunter