Specific stellar angular momentum vs. the observed ellipticity of the ATLAS^3D galaxies. Small open circles are galaxies with no available HST observations, and small filled circles are galaxies for which the central surface brightness profile is uncertain, mostly because of a dusty nucleus. Red diamonds are core galaxies (γ′ ≤ 0.3), and blue pentagons are core-less galaxies (γ′ > 0.3). The green solid line separates fast from slow rotators following Emsellem et al. (2011), and the grey solid line is the Cappellari (2016) alternative. The dashed magenta line shows the edge-on view for spheroidal galaxies integrated up to infinity with β = 0.7 × ϵ_intr, as in Cappellari et al. (2007). Other dashed lines show the same relation projected at inclinations of 80°, 70°, 60°, 50°, 40°, 30°, 20°, and 10° (from right to left). The dotted lines show the change in location for galaxies of intrinsic ϵ_intr = 0.85, 0.75, 0.65, 0.55, 0.45, 0.35, and 0.25 (from top to bottom). This plot differs from Fig. 4 (left) of Krajnović et al. (2013b) in that all slow rotator galaxies now have nuclear surface brightness characterisation, but the number of slow rotators with cores did not increase. NGC 1222 is the small black symbol on the grey line.