Spin–lattice relaxation in the rotating frame
Spin–lattice relaxation in the rotating frame is the mechanism by which "Mxy" , the transverse component of the magnetization vector , exponentially decays towards its equilibrium value of zero , under the influence of a radio frequency ( RF ) field in nuclear magnetic resonance ( NMR ) and magnetic resonance imaging ( MRI ) . 
<triplet> magnetic resonance imaging <subj> nuclear magnetic resonance <obj> based on