Left panels: behaviour of the [K/Fe] as a function of v_t provided by CAR. Red circles are the stars of NGC 104, green triangles those of NGC 6752, blue pentagons those of NGC 6809. Right panels: behaviour of the [K/Fe] as a function of v_t derived according to Kirby et al. (2009). The stars of NGC 2808 (black squares, Mucciarelli et al. 2015) are shown for comparison in the lowest panels. The arrow in the upper-left panel shows the effect on [K/Fe] of the change in v_t.