CINCH NucWik

Tor Bjørnstad
Section of Radiochemistry
Institute of Chemistry
Faculty of Mathematics and Natural sciences
University of Oslo

1. Understand mother-daughter relations and radioactive equilibrium
2. Understand how a radio-nuclide generator works and how it is used
3. Understand how radioactivity is "growing in"
4. Training in handling radioactive material and safety procedures

The task in this Laboratory Exercise is to record a disintegration curve of ^234mPa and from this curve determine the half-life of the nuclide.
The ^234mPa radionuclide is obtained from a generator system consisting of an ion exchanger column with fixed ²³⁴Th where the daughter is milked by a liquid elution process.
The α particles from the produced ^234mPa-source is recorded by a GM-detector.

The principle behind Mother-Daughter Relationship is illustrated below.

Basic Theory

A radionuclide generator, also popularly called a “cow”, is composed of a mother-daughter radionuclide relationship where the mother has a longer half-life than the daughter. The daughter is continuously produced by decay of the mother in the generator system, and the daughter can be separated (“milked”) from the generator by chemical or physical methods. In this Exercise we are going to use one such system defined in more detail below. From basic lectures on decay we have the following relation between a radioactive nuclide and its radioactive daughter: