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The next decisive steps where made almost at the same time, and along two distinct paths, by E. M. Purcell, H.C. Torrey and R.V. Pound and by F. Bloch, W.W. Hansen and M. Packard, earning the two first authors a shared Nobel prize in 1952
Both make use of the nuclei inside a condensed matter sample (paraffin, for Purcell and water, for Bloch) immersed in a static magnetic field , both employ the detection of the nuclear magnetization by means of its inductive coupling to a circuit located around the sample: a cavity obtained with a coaxial geometry for the former and a simple coil for the latter.
At thermal equilibrium in the magnetic field a small paramagnetic nuclear magnetization is produced. The Purcell experiment measures the resonant radiofrequency power absorption of the nuclear spins, whereas Bloch directly obtains the coherent nuclear induction signal which is the heart of the modern pulsed NMR technique.