Hope College Physics Department
Research Experiences for Undergraduates
|Project Title:||Development and Implementation of a Low-Background Radiodating Facility at Hope College|
|Student Name:||Kelly Petrasky|
|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
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: