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Nuclear Reactions: 197Au (~~ fission-like reactions), E=343MeV, measured energy and angular correlations for heavy-fragment pairs. Evolution shown from fission-like to projectile-target-like products. Analysis made of the fission-like reactions in terms of complete vs. incomplete fusion.Measurements are reported for correlated energies and angles of heavy fragments from reactions of 343 MeV ~~ with 197Au. The results show a continuous evolution of the mass distributions from fission-like products at angle pairs of ~60 and 300 degrees to deeply inelastic projectile-like products at ~45 ~ and 300 ~ Certain difficulties are emphasized for the use of the "symmetric fragmentation" cross sections in the context of current theoretical models (e.g. the "extra push" theory). The fission-like reactions have been studied in some detail and the results have been compared to a Monte Carlo kinematic simulation. To account for the experimental results forward-peaked light particle emission (n, H, He) must occur in a large fraction of the fission-like reactions.

A Proof-of-Principle (POP) Contraband Detection System (CDS), is under construction at Northrop Grumman's Advanced Technology and Development Center. We employ ganmia resonance absorption (GRA) to detect nitrogen or chlorine in explosives and certain forms of illegal drugs. Using tomography, 3-D images of the total density and selected element density are generated. These characteristics together may be utilized with considerable confidence in determining if contraband is present in baggage or cargo.The CDS employs a high current ( 1O mA) DC electrostatic accelerator that provides a beam of protons at either 1 .75 or 1.89 MeV. These high energy particles impinge upon a target coated with '3C or S. The resultant resonant gamma rays are preferentially absorbed in either N or 35Cl. Because of the penetrating power of the gamma rays, this approach can be utilized for inspection of fully loaded aircraft containers such as the LD3 . With proper design for handling baggage and with certain CDS design features not present in the POP, throughputs approaching 2000 bags/hour are estimated. Furthermore, the technology being developed for the CDS accelerator may have other applications such as for Boron Neutron Capture Therapy or Neutron Radiography.Our current program calls for testing of the POP CDS by late 1996. This paper presents the overall design, and characteristics of the CDS POP and the status of the program.