Fig. 1.
(a) The first 100 normalized singular values σi and σ̂i, plotted in descending order, of α* and α̂*, respectively. (b) The same, for β and β̂ The matrices were obtained by Bloch simulation of small-tip-designed accelerated spiral and EP pulses, that were scaled to excite large-tip-angles. The gradient frame parameters α̂* and β̂ possess few significant singular values compared to the standard rotating frame parameters α* and β, permitting accurate low-rank approximations to these matrices.