[en] The results which are collected during the test phase of the THTR-300 are the base for the comparison with the results of simulation calculations which are made with THTR dynamic model ALAMO. This report shows, that the simulation of the power plant is in very good agreement with the measuring results for the following cases: transients in normal operation, breakdown of a blower unit and breakdown of a feedwater-pump. In addition the steam generators of the THTR are explained, the reasons for the heat loss are shown and the parasite heat transfer is calculated. (orig.)

[en] The 'THTR-Anlagenmodell' (ALAMO) is used to simulate the plant behaviour of High-Temperature-Gas-Cooled-Reactors. For the verification of the program code calculations of ALAMO were compared with data from experiments of the starting phase. These experiments included the steady state and transient behavior of the reactor like load change, loss of turbine, loss of one out of two feedwater pumps, loss of one of two generators for the power supply of the helium blowers, start-up procedures, fast cooling procedures and emergency core cooling procedures. The results showed sufficient agreement between the experimental and calculated data. In summary, the program code ALAMO provides an adequate prediction of steady state and transient plant behavior of the THTR-300. (orig.) With 34 refs., 6 tabs., 126 figs

[en] By using accurate prism-coupled optical waveguide refractive-index measurements on cation-doped indium oxide films and a classical polarizability model having adjustable local field weighting factors, estimates have been obtained for the electronic polarizabilites of ten cations and the relative local fields in their respective oxides. Self-consistent results for the ten oxides were obtained for a constant oxygen polarizability of 1.5 (A)³. The relative local fields were found to be larger at the oxygen than at the cation sites, consistent with the observation that the refractive index is more sensitive to anion than cation changes. The results should be useful for optical applications requiring dopant control of refractive index

[en] We present a slab-line waveguide whose geometry is optimized for wide-angle x-ray diffraction (XRD) experiments on protein crystals during irradiation with intense microwave fields. Characterization of the waveguide transmission and reflectivity (using time-domain reflectometry) and of the electric field distribution inside the waveguide (using finite-difference time-domain calculations) shows that the present device has a broad bandwidth from below 0.5 to 18 GHz, allowing one to perform frequency-dependent XRD studies with a well-defined transverse mode structure and negligible reflection losses. As shown with a specific example, our device provides a simple way to couple microwave irradiation experiments with high-resolution x-ray diffraction measurements from millimeter-size crystalline samples. The present design might prove useful for systematic studies of microwave effects on protein structure and dynamics

[en] The inclusive and semi-inclusive cross sections for K/sup asteriskplus-or-minus/(890) and Σ^+-(1385) resonances are determined in p-barp interactions at 14.75 GeV/c. They account for a large fraction of the K⁰/sub S/ and Λ⁰ produced. The K/sup asterisk/-resonance production also affects the low-p/sub T//sup ts2/ distribution of inclusive K⁰/sub S/. The x distributions of the resonance production are studied in terms of a simple quark-recombination model

[en] Radial waveguide set-ups are introduced as exposure devices for long-term experiments with large numbers of non-restrained animals exposed simultaneously. Methods are presented to ensure well-defined exposure conditions even for potentially over-moded waveguides and for the exposure of large groups of animals per cage. The proposed methods are applied for a four-generation study being performed on up to 2500 mice exposed to a generic UMTS test signal at prescribed averaged whole body specific absorption rates (SARs). The variation of the whole body SAR due to the movement of the mice inside the cage is calculated by using the finite-difference time-domain method and detailed animal models for selected configurations of the mice inside the cage for all stages of the study. (authors)

[en] The scientific program and current status of the planned accelerator laboratory in the Felsenkeller shallow-underground facility in Dresden, Germany, are reviewed. (paper)

[en] A 2 m × 0.5 m large prototype of an MRPC-based (Multi-gap Resistive Plate Chamber) neutron Time-Of-Flight-wall for detecting relativistic neutrons in an energy range from 200 MeV to 1 GeV was successfully designed and realized. It consists of steel plates which convert neutrons via hadronic interactions into charged particles, followed by a 2 × 2 gap MRPC-structure to detect the charged particles. Tests were carried out using 30 MeV electrons with an energy close to the minimum of ionization in order to study the properties of the prototype achieving an efficiency larger than 90 % and a time resolution σ_t better than 100 ps. For units with an active area of 40 cm × 20 cm and otherwise the same design, quasi-monochromatic neutrons with a peak energy of 175 MeV were utilized to study their response to relativistic neutrons. Detailed Monte Carlo simulations were performed both for the small and for the large modules to simulate their properties to both neutrons and electrons and to study the performance of the final neutron detector assembly with an area of 2 m × 2 m for single-neutron and multi-neutron events. (technical report)

[en] Resistive plate chamber (RPC) prototypes of 2 m length were simulated and built. The experimental tests using a 31 MeV electron beam, discussed in details, showed an efficiency higher than 90% and an excellent time resolution of around σ=100ps. Furthermore, comprehensive simulations were performed by GEANT4 toolkit in order to study the possible use of these RPCs for fast neutron (200 MeV–1 GeV) detection and multi-neutron event identification. The validation of simulation parameters was carried out via a comparison to experimental data. A possible setup for invariant mass spectroscopy of multi-neutron emission is presented and the characteristics are discussed. The results show that the setup has a high detection efficiency. Its capability of determining the momentum of the outgoing neutrons and reconstructing the relative energy between the fragments from nuclear reactions is demonstrated for different scenarios.