Development of an Auto Sample Exchanger for Gamma Counting to Enhance NAA Capacity of BAEC

An automatic sample changer for the HPGe gamma counting system was developed under the CRP. A pneumatic system based sample changer for gamma counting was constructed and installed in the existing HPGe detector (Canberra, 25% relative efficiency; 1.9 keV resolution at 1332 keV of ⁶⁰Co) coupled with a digital gamma spectrometer (ORTEC DSpec Jr^TM) and Maestro-32 acquisition software (ORTEC). A new, moveable counting chamber was fabricated to change the sample to detector distances between 5, 10, 15 and 20 cm depending on the dead time. A new software package was developed for the control and management of the counting procedure by interfacing all the fabricated mechanical devices with the existing data acquisition software. The home-made auto sample changer coupled with the HPGe system is now facilitated the measurement of the irradiated samples automatically without any human intervention. The new technology was adopted under the IAEA-CRP. (author)