Two-dimensional kinematics of SLACS lenses – III. Mass structure and dynamics of early-type lens galaxies beyond z ≃ 0.1

摘要: We combine in a self-consistent way the constraints from both gravitational lensing and stellar kinematics to perform detailed investigation of internal mass distribution, amount dark matter, dynamical structure 16 early-type lens galaxies Sloan Lens ACS Survey (SLACS Survey), at z = 0.08-0.33, for which Hubble Space Telescope/Advanced camera Surveys NICMOS high-resolution imaging Very Large Telescope VI-MOS integral-field spectroscopy are available. Based on this data set, we analyse inner regions galaxies, that is, typically within one (three-dimensional) effective radius r(e), under assumption axial symmetry by constructing models supported two-integral distribution functions. For all systems, total density is found be well approximated simple power law rho(tot) proportional m(-gamma)' (with m being ellipsoidal radius): profile average slightly super-isothermal, with logarithmic slope 2.074(-0.041)(+0.043) (errors indicate 68 per cent confidence interval) an intrinsic scatter sigma(gamma)' 0.144-(+0.055)(0.014), fairly round, ratio 0.77 +/- 0.04. The lower limit matter fraction (f(DM)) inside r(e) ranges, individual nearly zero almost half, median value 12 cent. By including masses derived population synthesis Salpeter initial function (IMF), obtain f(DM) 31 cent, corresponding profiles physically acceptable, exception two cases where they only marginally exceed profile. rises 61 if, instead, Chabrier IMF assumed. IMFs, increases galaxy (correlation significant 3 sigma level). angular momentum parameter calculated our models, find can divided into dynamically distinct groups, shown correspond usual classes (observationally defined) slow fast rotators. Overall, SLACS systems structurally very similar their nearby counterparts, indicating have undergone little, if any, evolution since redshift approximate 0.35.