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arXiv · 1710.01337

A Flexible Positron Spectrometer for the Undergraduate Laboratory

Jason Engbrecht·Nathaniel Hillson
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Abstract

Positron physics touches on a wide-ranging variety of fields from materials science to medical imaging to high energy physics. In this paper we present the development of a flexible positron annihilation spectrometer appropriate for the undergraduate laboratory. Four NaI gamma-ray ($\gamma$-ray) detectors are connected to an oscilloscope-based data acquisition system. Coupled with the software we developed, these detectors allow students to explore a variety of positron and $\gamma$-ray phenomena. These include $\gamma$-ray energy spectroscopy, Compton scattering, PET scanning fundamentals, speed of light measurements with $\gamma$-rays, historically important polarimetry of annihilation radiation, 3-$\gamma$ annihilation radiation observations, and positron lifetime spectroscopy of materials. We present the developed apparatus and examples of experiments it can perform here.

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Jason Engbrecht, Nathaniel Hillson. 2017-10-03. A Flexible Positron Spectrometer for the Undergraduate Laboratory. https://doi.org/10.1119/1.5038672

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