Khalid H. AL-Ubaidi, Salam K. AL-Nasri, Auday T. AL-Bayati
الملخص الانجليزي
Observed in the recent period, there is an urgent need to a prepare standard sources can be adopted in the
research Iraqi universities and scientific Institutions, whether if these measurements for large sizes samples such
as Marinelli beaker , or small sizes such as a petri dish and the latter was not available as standard sources,
which was the purpose of this work to prepare standard source with size of a petri dish for plants using 152Eu
Isotope , that can be adopted in the experimental measurements.The prepared sample was measured in the first
lab ( Department of physics/ college of education for pure science/Ibn Al-Haitham/University of Baghdad) and
the second lab (Central Laboratories Directorate / nuclear research center at Tuwaitha) by using Gamma
spectroscopy system with a high-purity germanium detector (HPGe). The specific activity of the prepared
standard sample was calculated using an efficiency curve , which drawn by using the Monte Carlo Program . The
results of the specific activity are equal to (1167.610Bq/kg) in first lab and (1081.94 Bq/kg) in second lab. It was
noted there is good agreement between the results in the first and second lab, so the overall average of the
specific activity adopted was equal to (1124.7 Bq / kg)From this work, we can use this source to calculate the
radioactivity for other radionuclide in small samples (plants), which is difficult to obtained in large quantities,
through a calibration spectrum for efficiency and energy of this prepared source.