What instrument can be used to assess radionuclidic purity by evaluating the energy spectrum of a sample?

The multichannel analyzer is the appropriate instrument for assessing radionuclidic purity by evaluating the energy spectrum of a sample. This device functions by measuring the energy of gamma rays emitted from radionuclides. When a sample is subjected to a gamma-ray detection process, the multichannel analyzer sorts these gamma-ray energies into a spectrum, allowing for a detailed analysis of the radionuclide composition present in the sample.

This capability is crucial for determining the purity of a radionuclide, as it can identify different isotopes based on their specific energy emissions. By comparing the energy peaks in the spectrum against known reference values for various radionuclides, one can assess whether a sample is predominantly a single isotope or if it contains contaminants from other radionuclides.

In contrast, other instruments listed serve different purposes. A gamma camera is primarily used for imaging and does not provide detailed spectral information about the energy of the emitted gamma rays. A Geiger counter is designed for detecting ionizing radiation but lacks the capability to perform energy spectrum analysis. A dosimeter is utilized to measure radiation exposure over time and does not analyze the radionuclidic content of samples.