Measurement Model of an Alpha Spectrometer for Advanced Undergraduate Laboratories

Jithin B.P. , V.V.V. Satyanarayana, Swapna Gora, Ajith B.P.

Central University of Himachal Pradesh

In this paper, we present the modeling aspects relevant to students at the advanced UG level for using an Alpha Spectrometer as a measurement tool for nuclear physics experiments. The four stage modeling methodology for construction of theoretical models is utilised as a framework to understand the various aspects of an alpha spectrometer. The presentation specifically focuses on alpha spectrometer AlphaSpec-1K indigenously designed and developed by us. The spectrometer output is interfaced to the USB port of a PC, and the associated software CNSpec, which is licensed under open-source terms, has built-in features to fit, calibrate, and perform various analysis of the obtained spectrum. The spectrometer is designed to detect alpha energies in a full scale range of 10 MeV with a resolution of 81 keV at 5485 keV. It is calibrated using 241-Am and tested for linearity using 229-Th multi-peak source, and as a final step, has been validated using 212-Bi, by verifying its spectrum with published literature, as well as calculating its half life to better than 1% accuracy.