Nuclear Physics Experiments Below The Coulomb Barrier

In 1932, Cockcroft and Walton showed that (p,α) reactions with lithium were possible at energies near 100 keV. We report an undergraduate laboratory experiment with 90 keV protons colliding with a thick lithium target. The experiment allows students to observe the products of two reactions, to determine the product masses, and to learn techniques for deconvolving experimental spectra profiles.