Two-dimensional stellar kinematics of 48 representative E and S0 galaxies obtained with the SAURON integral-field spectrograph reveal that early-type galaxies appear in two broad flavours, depending on whether they exhibit clear large-scale rotation or not. We define a new parameter λR ≡ 〈R |V |〉/〈R √ V 2 + σ 2 〉, which involves luminosity weighted averages over the full two-dimensional kinematic field, as a proxy to quantify the observed projected stellar angular momentum per unit mass. We use it as a basis for a new kinematic classification: early-type galaxies are separated into slow and fast rotators, depending on whether they have λR values within their effective radius Re below or above 0.1, respectively. Slow and fast rotators are shown to be physically distinct classes of galaxies, a result which cannot simply be the consequence of a biased viewing angle. Fast rotators tend to be relatively low luminosity galaxies with MB ∼> −20.5. Slow rotators tend to be brighter and more massive galaxies, but are still spread over a wide range of absolute magnitude. Three slow rotators of our sample
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