Glossary Terms  Home

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On-Resonance Excitation

The presentation of an excitation pulse at the resonance frequency of the sample, resulting in maximal efficiency.

Off-Resonance Excitation

The presentation of an excitation pulse at a frequency other than the resonant frequency of the sample, resulting in reduced efficiency.

Oscillating Magnetic Field

A magnetic field whose intensity changes over time. Most such field used in MRI oscillate at the frequency range of radio waves (megahertz, or MHz) and as such they are often called radiofrequency fields.