Further evidence for large central mass-to-light ratios in early-type
  galaxies: the case of ellipticals and lenticulars in the Abell~262 cluster
  We present radially resolved spectroscopy of 8 early-type galaxies in
Abell~262, measuring rotation, velocity dispersion, $H_3$ and $H_4$
coefficients along three axes, and line-strength index profiles of Mg, Fe and
H$\beta$. Ionized-gas velocity and velocity dispersion is included for 6
galaxies. We derive dynamical mass-to-light ratios and dark matter densities
from orbit-based dynamical models, complemented by the galaxies' ages,
metallicities, and $\alpha$-elements abundances. Four galaxies have significant
dark matter with halos about 10 times denser than in spirals of the same
stellar mass. Using dark matter densities and cosmological simulations,
assembly redshifts $\zdm\approx 1-3$, which we found earlier for Coma. The
dynamical mass following the light is larger than expected for a Kroupa stellar
IMF, especially in galaxies with high velocity dispersion $\sigeff$ inside the
effective radius $\reff$. This could indicate a `massive' IMF in massive
galaxies. Alternatively, some dark matter in massive galaxies could follow the
light closely. Combining with our comparison sample of Coma early-types, we now
have 5 of 24 galaxies where (1) mass follows light to $1-3\,\reff$, (2) the
dynamical mass-to-light ratio {of all the mass that follows the light is large
($\approx\,8-10$ in the Kron-Cousins $R$ band), (3) the dark matter fraction is
negligible to $1-3\,\reff$. Unless the IMF in these galaxies is particularly
`massive' and somehow coupled to the dark matter content, there seems a
significant degeneracy between luminous and dark matter in some early-type
galaxies. The role of violent relaxation is briefly discussed.
