Fig. 1: Distinctive characteristics of Carr’s steady-state free-precession (SSFP) experiment.
a SSFP sequence involving a train of pulses α (assumed here applied with constant phase x) spaced by repetition time intervals TR, leading to short time-domain signals S(t). Shown underneath in green is a subset of the coherence transfer pathways p undergone by an isolated spin ensemble under the action of the sequence, illustrating the complex echoing at the top of any given pulse. b Steady-state responses S(0) arising at the top of each SSFP pulse as a function of a site’s frequency offset, shown for four different flip angles α. Shown as well are the transverse magnetizations Mx (black), My (blue) and their magnitude sum | Mx,y | (red) arising for each flip angle over the full frequency range, and their integrated absolute values. Offsets past ±1/2TR repeat themselves inside this region by repetitive fold-overs.
