THE V-R DIAGRAM - A DIAGNOSTIC-TOOL FOR THE DYNAMICAL CLASSIFICATION OF SPIRAL GALAXIES

The relations between the angular momentum (J) and the mass (M) for a sample of spiral galaxies are discussed for galaxies distributed in the rotational velocity (V) - size (R) plane. It is found that, for a given mass, Sc galaxies have larger angular momentum (approximately 20%) than Sa. The absence of segregation in the angular momentum (J) - mass (M) plane is explained in terms of observational errors, which are greater than the expected differences in J between galaxies of equal mass and different type. The distribution of lenticular and irregular galaxies in the V-R plane is also discussed.