Fig. 1.
Illustration of the trade-off between present and future image intensity in a single compound. (a) Each acquisition relies on choosing an angle α to perturb the longitudinal magnetization into the transverse plane, allowing a measurement of magnitude x(t) sin(α), after which x(t) cos(α) longitudinal magnetization remains for future acquisitions. (b) Repeated excitation leads to repeated discrete jumps in the system state, depleting the remaining magnetization.