EFFECT OF SAMPLE POSITION ON EFFICIENCY IN GAMMA-RAY SPECTROSCOPY

Öz

The full energy peak efficiency for the energies of interest must be known to determine the concentration of activity in gamma-ray spectrometry. This work is focused on examining the effect of sample position on full energy peak efficiency. For this purpose, efficiency values were determined by experimental and Monte Carlo simulation method using three different HPGe detectors and standard charcoal cartridges. The cartridges were first counted in the centers of the detectors and then replaced on the X-axis at 5 mm intervals. At maximum distances from the center of 25 mm for Ge-1, 15 mm for Ge-2, and 10 mm for Ge-3, experimental full energy peak values are 11.8-16.4% in Ge-1, 8.2-13.8% in Ge-2, and decrease between 4.9-11.0% in Ge-3. The results show that the sample position significantly affects the full energy peak efficiency, using a sample locator if possible, if not counting as carefully in the center as possible.

Anahtar Kelimeler

• Gamma-ray spectroscopy
• full energy peak efficiency
• sample position
• charcoal cartridge filter.

Kaynakça

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