[en] Fraunhofer-INT is going to equip a transportable container with a system for the detection, identification and characterization of radioactive material inside objects with unknown content. This system will be a prototype for a mobile system to detect illicit trafficking of radioactive and especially nuclear material and will thus prohibit nuclear proliferation. This container will be equipped with systems for passive and active nondestructive measurements. For active measurements we use a sealed tube 14 MeV neutron generator with an without a moderating assembly between the interrogating neutron source and the object of interest. Because stolen or diverted radioactive material generally may not have a fixed geometry and will not be packaged in standard containers the main emphasis in this paper is on in-situ gamma measurements taking into account possible shielding around the radioactive source. High-resolution gamma measurements were performed on radioactive material behind different types of shielding. The measured data were evaluated by modeling the different parameters like the wall thickness of the box, matrix and shielding material inside and so on. Comparison with the actual experimental setup of the models showed good agreement and proved the power of this method. In this way significant information was gained on the content of the unknown box, which is important for further actions. (author)

[en] At the 3.5 GeV electron accelerator ELSA of Bonn University, polarized electrons have been accelerated up to 2.0 GeV, crossing several depolarizing resonances without significant depolarization. The polarized electrons were produced by photoemission from an AlGaAs-GaAs superlattice crystal using circularly polarized laser light. A harmonic correction scheme was successfully applied to the third imperfection resonance (γa = 3) and the polarization required for the planned experiments was conserved up to 2.0 GeV. (orig.)

[en] Polarized electrons have been accelerated in the electron stretcher accelerator ELSA for the first time. Up to 2.1 GeV the polarization of the electron beam supplied by the 120 keV polarized electron source has been measured with a Moeller polarimeter. Preliminary results of polarization measurements at high energies and the performance of the source are presented

[en] A Reply to the Comment by J. Jourdan, I. Sick, and J. Zhao. copyright 1997 The American Physical Society

[en] The ratio of neutron and proton yields at quasifree kinematics was measured for the reactions ²H(e,e'n) and ²H(e,e'p) at momentum transfers Q²=0.125, 0.255, 0.417, and 0.605(GeV/c)², detecting the neutron and the proton simultaneously in the same scintillator array. The neutron detection efficiency was measured in situ with the ¹H(γ,π⁺)n reaction. From this the ratio R of ²H(e,e'n) and ²H(e,e'p) cross sections was determined and used to extract the neutron magnetic form factor Gⁿ_M in a model insensitive approach, resulting in an inaccuracy between 2.1% and 3.3% in Gⁿ_M