Figure 3.

Minimum detectable Mn²⁺ concentration as a function of TR (from eq 7), for a spin echo sequence. T₁₀=1.6s, SNR₀=5, N_Pe=256, T_ex=20 min, r₁=8 s^-1 mM^-1. The optimum TR is 800 ms (i.e. 0.5 T₁₀ as previously found[25]), and at this TR N_av≈5. The curve is quite broad; TR can be in the range 0.4-1.4s without C_min rising more than 10% above its optimised value, and in the range 0.3-1.7s without rising 20% above its optimised value.