Win-8a low background αβ measuring instrument is mainly composed of detector unit, signal processing unit and shielding unit. During the measurement, the detector records the incident α and β particles, and the count rate is proportional to the nuclide activity in the sample. The detector unit is composed of a main detector, an anti-coincidence detector and is placed in a shielding unit. The signal processing unit consists of a computer and a measuring mainframe. Shielding units are made of materials such as lead and steel.

Detection principle: The scintillation body at the top of the detector is composed of α scintillation material and β scintillation material pressed on a plexiglas plate. When α particles and β rays enter the scintillation material, all the energy is lost on the scintillation material, which causes scintillation and luminescence. The scintillation photon is received by the photomultiplier tube and converted to generate electrical signal. The electrical signal enters an electrical circuit, is converted into an electrical pulse, and is recorded. The optical signal produced by each alpha particle hitting the scintillator is integrated into the electrical circuit and recorded as a count on the display. So the low background αβ measuring instrument is also colloquially called the low background αβ counter. The count rate is proportional to the nuclide activity (the number of emitted αβ particles) in the sample.

Analysis method: The instrument can measure the total αβ activity concentration in different samples after calibration with reference materials. The results are expressed in Bq/L, Bq/kg, Bq/m3, etc.