Currently, the Munich pulsed low energy positron beam-system (PLEPS) is transferred to the high-intensity positron source (NEPOMUC) at the Munich research Reactor FRM II. We expect count-rates up to 106 cps. Several improvements to enhance the performance of the system have been implemented. Until now, PLEPS was employed exclusively for lifetime measurements. To enable also Doppler-broadening, coincident Doppler-broadening and AMOC experiments, two additional detector ports have been installed. An additional chopper allows to suppress pulses and, therefore, to extend the standard time window of 20 ns for precise measurements of longer lifetimes. The high event-rate supports the use of smaller scintillators. Consequently an improvement in time resolution is expected. Also envisaged is the use of new detector materials. Various measures to further reduce background from back-scattered positrons and a reduction of the beam diameter down to 1 mm will improve the overall performance of the system.    «

Currently, the Munich pulsed low energy positron beam-system (PLEPS) is transferred to the high-intensity positron source (NEPOMUC) at the Munich research Reactor FRM II. We expect count-rates up to 106 cps. Several improvements to enhance the performance of the system have been implemented. Until now, PLEPS was employed exclusively for lifetime measurements. To enable also Doppler-broadening, coincident Doppler-broadening and AMOC experiments, two additional detector ports have been installed....    »