Determination of 210 Po in Groundwater Samples for Nuclear Astrophysics Applications

Abstract

Borexino is a liquid scintillator detector at Laboratori Nazionali del Gran Sasso in Italy designed to study a variety of neutrinos. It requires extremely pure scintillator with low concentrations of interfering natural radioactive isotopes such as 238U, 40K, and 210Po. Large quantities of natural water containing trace 210Po are used for liquid-liquid extraction with this scintillator, potentially resulting in the contamination of the scintillator fliud with 210Po; accurate determination of the 210Po concentration in this natural water is critical to developing methods of reducing its concentration. The objective of this study was to determine a safe, simple, and easily reproducible method for determining 210Po in natural water sources without the use of 208Po or 209Po tracer. A procedure for obtaining full recovery of 210Po from a piece of radioactive lead with known polonium activity is determined, and the results of these efforts are used to produce a procedure for the determination of 210Po activity in groundwater sources.