Behavior of radon progeny produced in a scintillation cell in the flow-through condition

Sakoda, Akihiro   ; Meisenberg, O.*; Tschiersch, J.*

When a scintillation cell is used for radon measurement, detection efficiencies for individual alpha emitters (Rn, Po and Po) are required depending on the methods of data analysis. The present study describes an attempt to obtain an empirical parameter which is necessary to calculate their individual detection efficiencies in the flow-through cell: the fraction of the progeny generated in the cell which is deposited onto the wall. As a result, an empirical formula was acquired to estimate the deposition fraction of Po as a function of flow rate. This result is helpful in understanding the characteristics of the scintillation cell. The empirical formula derived in this study can also be applied to predicting the behavior of thoron progeny (Pb and its progeny) in continuous thoron measurements with the flow-through scintillation cell.