High resolution alpha particle spectrometry through collimation

• Alpha particle spectrometry with collimation a useful method for identifying nuclear materials among various radionuclides.
• A collimator cut off alpha particles with low angle emitted from a source.
• We confirm that that a collimator improves the resolution of alpha spectra through both simulation and experiments.

Alpha particle spectrometry with collimation is a useful method for identifying nuclear materials among various nuclides. A mesh type collimator reduces the low energy tail and broadened energy distribution by cutting off particles with a low incidence angle. The relation between the resolution and the counting efficiency can be investigated by changing a ratio of the mesh hole diameter and the collimator thickness. Through collimation, a target particle can be distinguished by a PIPS® detector under a mixture of various nuclides.