Plots of signal measured by the DS-CPMG sequence at the 1st, 2nd, 8th and 16th echo (solid lines), along the y (left-hand plot) and z (right-hand plot) phase encode axes (i.e., profiles of the soft π and soft π/2 excitations respectively). The signal plotted is that observed along a line passing through the center of the sample. Also shown is the signal measured at the 4th echo of the HP-CPMG acquisition (dashed line), acquired 1.744 ms later in time than the 1st echo of the DS-CPMG acquisition. Circles in the first π/2 profile demarcate the centers of the 26 voxels comprising the measurements along that axis.