Prof. M. W. P. Strandberg W. J. C. Grant

Measurements of the dependence of the paramagnetic resonance linewidth in ruby have been carried out. These measurements are interesting in that they are made absolute by comparing the resonant susceptibility of the ruby with the resonant susceptibility of molecular oxygen, which can be precisely computed. By this means, the concentration of chromium ions can be determined, and the accompanying linewidth measured.