Relaxation in the Rotating Frame of Reference

If only B0 is applied, the nuclear moments precess without any phase coherence. No resultant component of the magnetization in the x y plane is observed and M, equals M0 (Fig. 1.7(a)). 

The decay of the magnitude of transverse magnetization, My, due to spin-spin relaxation (T2) or due to field inhomogeneities (T2 ) may be faster but cannot be slower than the spin-lattice relaxation (Tt)  

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