Nuclear Magnetic Resonance. A resonance phenomenon seen when you irradiate a sample in a magnetic field with an RF field. NMR teslameters are the most accurate and precise of magnetometers.
For NMR probe arrays, normalisation refers to a procedure to compensate for the very slight probe-to-probe variations caused by the magnetic susceptibility of some of the array's components in high fields. The procedure requires a large-bore, homogeneous magnet at the correct field strength, and simply consists of placing each probe in turn at exactly the same location and measuring its response. During operation, the Magnetic Field Camera automatically reads the normalisation data from the probe array and compensates all measurements.