χ² map of the X and Z scan for solar data. The orange and red crosses indicate the positions of AAG21 model including rotation and magnetic fields and the MB22 standard solar model respectively (values from their paper). The upper panels are associated with model M1 and the lower panels are associated with model A2 (see text for details). The left panels are associated with the high-T subdomain for the Z determination, while the right panels are associated with the low-T subdomain used to determine X.