ASTERIX

Abstract: In this paper, the design procedure and the performance of the single beam Asterix IV high-power iodine laser emitting at λ = 1315 nm is described. It has been developed on the basis of a 10-years experience with the 1 TW Asterix III laser-system and with the support of a 1-D and a 3-D pulse propagation code. Special emphasis has been put on achieving a high overall system efficiency and a beam intensity profile as homogeneous as possible. Presently, Asterix IV provides output pulses with durations from 0.2 to several ns. At a duration of 0.4 ns, the pulse power is 3 TW and at a duration of 5 ns the pulse energy reaches 2.1 kJ. Under these conditions, the laser can be fired every twenty minutes.

Abstract: For more than 500 shots the 1 TW iodine laser Asterix III has demonstrated high reliability for light-plasma-interaction experiments. Improved laser parameters and new measurements of light pulse properties are reported.

Abstract: The ASTERIX spectrometer has been used to study the formation and the ground state of the pp atom and exclusive final states of pp annihilation at rest in a H2 gas target at NTP, using antiprotons from the Low Energy Antiproton Ring (LEAR) at CERN. The article describes the mechanical construction of the apparatus, the trigger logic, the chamber readout, and the data acquisition system. The detector calibration and the offline processing of the 55 million reconstructed events are illustrated. An overview is given about the new physics results obtained by the experiment.

Abstract: This paper describes a real-time kernel, Asterix, that in a practical manner makes use of many of the recent advances made in the real-time systems research community. The basic ambition behind the development of the Asterix real-time kernel was to pack state-of the art research results into package such that it can be easily used and understood by people in the embedded systems industry. From an academic point of view the Asterix realtime kernel fulfills all the basic requirements necessary for facilitating different types of timing analyses. For a software designer this signifies that the Asterix real-time kernel has the means to satisfy engineering of real-time software in the same fashion as civil engineers make use of structural calculus when designing bridges or houses. The Asterix real-time kernel is in combination with its support environment in a unique position to provide the embedded systems industry with a development kit that can increase the reliability, safety, and testability of their applications with several magnitudes compared to existing development systems.