Rotational dependence of the α profiles calculated with test-field method and calculated from helicities. In the first row, we plot the traces of the α tensors, α_tr, which were determined using the test-field method for a selection of HD (Set H) and MHD runs (Set M). In the second row, we plot the kinetic α_K and the sum of kinetic and magnetic alpha α_KM for the corresponding runs of Set H and Set M, respectively. In the last row, we show the root-mean-square values of the trace of the α tensor, α_tr (black lines), the kinetic α_K (red), the magnetic α_M (blue), and their sum α_KM (orange) for all runs. The values of the HD runs are shown with a solid line and crosses, whereas the MHD runs are shown with a dashed line with diamonds. The greed dotted line indicates a power law with an exponent of 0.5. All values are normalized by . The zero rotation run has been moved to Co = 10⁻⁴ to be visible in the lower panel.