Neutron Activation of KCl to Produce 36Cl to Verify Energy-Mass Equivalence

Energy-mass equivalence, represented by E = mc^2, is a fundamental concept of modern physics that is relevant in nuclear physics and beyond. A direct test of this relationship can be performed by comparing the energy of gamma-rays emitted after cold neutron capture with the mass difference of the initial and final states. The energies of the gamma-ray released after cold neutron capture on 35Cl have been precisely measured at the Institut Laue Langevin. We plan to measure the mass difference between 35Cl + n and 36Cl at FRIB using the LEBIT Penning trap mass spectrometer. The goal of this project was to make 36Cl at CMU using an Am-Be neutron source and determine the quantity produced. We placed samples of KCl and NaCl in the neutron source for approximately 1 year, then used a HPGe detector to perform gamma ray spectroscopy on the samples.

In the presentation, we will present our data that shows the production of our radioactive isotopes and describe our analysis to determine of the number of 36Cl atoms that were produced. We identified 42K and 38Cl in the KCl sample and used the results to quantify the number of atoms of these isotopes that were produced and normalize the neutron flux. We will also discuss the outlook for the penning trap measurements at FRIB.