Low background liquid scintillation analyzer circuit design

Liquid scintillation technique was developed from the early fifties as an effective way to measure the low energy radiation. It can detect more than half of the periodic table of elements. And it is widely used in industry, agriculture, biology, chemistry, medicine, geology, hydrology, archeology, environmental protection and other fields. When measuring on low energy β-ray and low penetration α-ray with liquid scintillation analyzer, the number of its excitation photons is small. So, demand on the measuring instruments is very high. This paper analyzes the source of the liquid scintillation background counting, and it focuses on how to reduce background based on improving the sensitivity from the angle of the circuit design.