Spin Sorting: Apparent longitudinal relaxation without spin transitions

Nuclear magnetization in a magnetic field gradient evolving under spin sorting and true relaxation (the GCSW mechanism). The field varies from 10 T to 25 T over 15 cm. The lines are plots at several times of the numerical solution of Eq. (8) with T1 from Eq. (17) (both from the text). The negative magnetization on the left at t = 60 and 300 s is the signature of the spin sorting effect. At 10 000 s (not shown) the magnetization has reached Boltzmann equilibrium (solid line) and varies linearly with the field strength.