For the sample as a whole it is found that these models tend to predict too much motion on the major axis. This implies that elliptical galaxies as a class must have sigma_r > sigma_theta, which has not been demonstrated before. This result is consistent with general expectation as based on N-body simulations of dissipationless collapse.
From the models accurate mass-to-light ratios are derived that are corrected for the effects of rotation and radial anisotropy. The average mass-to-light ratio for the galaxies in the sample is (M/L)_B = (5.93 +/- 0.25) h_50. The mass-to-light ratios correlate with total luminosity according to (M/L) = cst x L^{0.35 +/- 0.05}. The quantity (v/sigma)* is identified as a second parameter in this relation. Galaxies with high (v/sigma)* tend to have a low mass-to-light ratio (for their luminosity).
The observed velocities in the outer parts of the galaxies in the
sample systematically exceed the velocities predicted by the (constant
mass-to-light ratio) models. From this it is argued that no
axisymmetric constant mass-to-light ratio models can fit the
kinematical data in the outer parts of elliptical galaxies. Either
dark halos must be present, or more detailed triaxial models must be
studied.
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