Magnetic resonance
= Magnetic resonance
<Magnetic resonance> is a resonantly driven transition between states whose energy separation depends on a <magnetic field>. A static field splits magnetic substates through the <Zeeman effect>, while an oscillating transverse field supplies energy near the transition frequency. For a simple spin with <gyromagnetic ratio> $\gamma$, the angular resonance frequency is $\omega_0=|\gamma|B_0$.
In the <Rabi molecular beam magnetic resonance experiment>, inhomogeneous magnets selected and refocused molecular trajectories. A radio-frequency field changed magnetic substates at resonance, altering the transmitted beam intensity. Scanning the frequency therefore measured magnetic moments through a frequency-dependent signal.<The Molecular Beam Resonance Method for Measuring Nuclear Magnetic Moments by Isidor Isaac Rabi and others>[Experimental method and resonance apparatus]{ref}