Dynamic irradiation counting systems for fast, short-time activation analysis using a fully automatic moveable counting chamber and a digital spectrometer

A fast, pneumatic system for short-time activation analysis has been constr ucted and installed in the TRGIA Mark-II reactor of the Technical Universit y of Vienna. The system is constructed to irradiate small samples and has b een fitted within a moveable thermal neutron absorber (Cd). The system faci litates the measurement of the irradiated samples by one of two detectors, or with both of them. The transfer time to the first detector is 0.35s, while 2 seconds are neede d to reach the second detector (HPGe, well-type detector). The first detect or is equipped with a new, moveable counting chamber to change the sample-d etector distances between 3, 6, 9, and, 12 cm. within 2s, automatically. Th e two detectors are connected to a new, fully digital spectrometer (DSPEC-p lus) which allows a high throughput and zero-dead-time (ZDT) counting mode. The spectrometer was implemented and optimised to change the shaping param eters, according to the specifications of the implemented detectors or the count rate situation, before or within a series of measurements. A new soft ware package was developed for the control and management of the irradiatio n-counting procedures.