(color online) The neutron powder diffraction pattern of PrGa at 295 K (a) and 4.5 K (b), respectively. The observed data and the calculated patterns are plotted in cross and solid line, respectively. The solid line at the bottom is the difference between the observed and calculated data. The Bragg positions for the nuclear and magnetic structure are marked as short vertical lines. Only nuclear model is considered in the refinement at 295 K and both nuclear model and magnetic model are considered in the refinement at 4.5 K.^[33]