Hope College Physics Department
Research Experiences for Undergraduates
Summer 2012
Project Summary


Project Title: Development and Implementation of a Low-Background Radiodating Facility at Hope College
Student Name: Nick Hubley
Student's Home Institution: Hope College
Research Advisor: Dr. Graham Peaslee and Dr. Paul DeYoung
Source of Support:

This material is based upon work supported by the National Science Foundation under NSF-RUI grants 0651627 and 0969058.

Measurement of γ rays produced by various radioactive isotopes within sediment can be used to determine the rate of sediment deposition or track sediment transport through the watershed. In order to accurately measure the type and intensity of radioactive isotopes within sediment samples, a low-background γ-ray counting facility is needed. This requires detectors encased in multi-layer shielding (plastic, copper, and lead layers) to minimize natural ambient radiation. Such a facility at Hope College has been developed with four high-purity Germanium detectors that are able to detect a wide range of environmental radioisotopes in sediment samples with high precision and low background. The construction of this facility and preliminary measurements of the detector efficiency and absolute solid angle measurements will be presented for each detector. Examples of their use in environmental measurements of sediment fingerprinting of radioisotopes such as 137Cs and 210Pb in the Lake Macatawa watershed will also be shown.

Publications and Presentations: