Study The effect of the shields movement and its thickness in detection efficiency By Using Scintillation Detector NaI(Tl)

摘要

In the present work, detection efficiency has been Calculated for the scintillation detector NaI(Tl) (2? x 2?) and radioactive source Cs-137, and by using absorbent material (shield) aluminum and iron between radioactive source and detector for thickness ( 0.1 – 1 ) cm. The effect of the shield movement and its thickness and also the speed of the shield movement on the detection efficiency have been studied. It is found that detection efficiency decrease with a moving shield and with the thickness of the shield. It is found, also that detection efficiency decrease with the speed of the shield movement for all shields aluminum and iron.