[en] The gyrocon is an rf-amplifier tube with a high output power in the wavelength region around 1 m. The principle of the tube is based on the controlled deflection of an electron beam, and on modern high-frequency techniques and beam transport methods. In the present paper the history, the principles and the design of the gyrocon are presented as well as the actual state of development. (GSCH)

[en] In order to efficiently employ a Time Projection Chamber (TPC) at interaction rates higher than ∝1 kHz, as foreseen e.g. in the ALICE experiment (CERN) and at CB-ELSA (Bonn), a continuous operation and readout mode is required. A necessary prerequisite is to minimize the space charge coming from the amplification system and to maintain an excellent spatial and energy resolution. Unfortunately these two goals can be in conflict to each other. Gas Electron Multipliers (GEM) are one candidate to fulfill these requirements. It is necessary to understand the processes within the amplification structure to find optimal operation conditions. To do so, we measure the charge transfer processes in and between GEM foils with different geometries and field configurations, and use an analytical model to describe the results. This model can then be used to predict and optimize the performance. The talk gives the present status of the measurements and describes the model.

[en] The method of Lissajous figures is usually used in measuring pulse linearity of photoelectricity multiply tube (PMT). In view of bigger uncertainty of Lissajous figures, this study proposes that constant current calibration may be used to determine standard line of Lissajous figures, accurately determine the pulse linear range of PMT. The study also provides an application example which indicates that this method effectively reduces uncertainty rooting in judgement of standard line and enhances accuracy of measurement. (authors)

No abstract available

[en] The invention is aimed at varying the magnetic field and hence the target removal area of a plasmatron atomizer. This could be achieved by providing certain parts of the magnet system with controllable heating means

No abstract available

[en] Published in summary form only

[en] Experimental and numerical techniques are used to characterize the radial structure of plasmas (250 MPa, 5 eV) generated in a high-pressure vessel. Such plasmas have been proposed to improve control of combustion in gun ballistic cycles by possibly controlling the mixing of fuel and oxidizer. In the experiments, the plasma is generated in a capillary (0.25 cm radius) lined with polyethylene which ablates and forms a dense mixture of ionized carbon and hydrogen. Measured values of peak power dissipation and electrical current are 100 MW and 40 kA. In the pressure and temperature range of interest, the plasma is optically thick (Rosseland mean free path is 10 μm) which precludes the use of optical diagnostic techniques to examine the radial structure of the plasma, so a numerical model is used. The model is based on conservation of continuum mass, momentum, and energy, and assumes the radiative diffusion approximation and a classical electrical conductivity derived from electron-ion and electron-neutral collisions. Numerical results will be presented which exhibit strong radial variations in the plasma temperature and species, and match measured power and electrical current

[en] An X-ray tube is connected to several different image processing devices in X-ray diagnostic equipment. Only a single organ selector is allocated to it, for which the picture parameters for each image processing device are selected. The choice of the correct combination of picture parameters is made by means of a selector switch. (DG)

No abstract available