χ² maps for target HD 92945 (left panel) and HD 141569 (right panel). The solid curves correspond to the isocontours at min(χ²)+1; +4; and +9 (eg. one, two, and three sigmas contours). Multiple minimums are present (false detections). The 5σ detection limits are, averaged over the separation, 2.5 × 10^-3 and 4.6 × 10^-3 (dashed curve). The right vertical axis was obtained assuming a linear fit of DUSTY evolutionarily models.