@Article{TortoraLaBNapCarRom:2012:BeCoMa,
               author = "Tortora, C and La Barbera, F and Napolitano, N. R. and Carvalho, 
                         R. R. de and Romanowsky, A. J.",
          affiliation = "Universitat Zurich, Institut fur Theoretische Physik, 
                         Winterthurerstrasse , Zurich, Switzerland and INAF – Osservatorio 
                         Astronomico di Capodimonte, Salita Moiariello Napoli, Italy and {} 
                         and {Instituto Nacional de Pesquisas Espaciais (INPE)} and 
                         University of California Observatories, Santa Cruz, CA 95064, 
                         USA",
                title = "SPIDER - VI. The Central Dark Matter Content of Luminous 
                         Early-Type Galaxies: Benchmark Correlations with Mass, Structural 
                         Parameters and Environment",
              journal = "Monthly Notices of the Royal Astronomical Society",
                 year = "2012",
               volume = "425",
               number = "1",
                pages = "577--594",
                month = "Sep.",
             keywords = "dark matter, galaxies, evolution, elliptical and lenticular.",
             abstract = "We analyze the central dark-matter (DM) content of \∼ 4, 
                         500 massive (M), low-redshift (z < 0.1), early-type galaxies 
                         (ETGs), with high-quality ugrizY JHK photometry and optical 
                         spectroscopy from SDSS and UKIDSS. We estimate the central 
                         fraction of DM within the K-band e\ffective radius, R , 
                         using spherically symmetric isotropic galaxy models. We discuss 
                         the role of systematics in stellar mass estimates, dynamical 
                         modelling, and velocity dispersion anisotropy. The main results of 
                         the present work are the following: (1) DM fractions increase 
                         systematically with both structural parameters (i.e. Re\ff 
                         , and S´ersic index, n) and mass proxies (central velocity 
                         dispersion, stellar and dynamical mass), as in previous studies, 
                         and decrease with central stellar density. 2) All correlations 
                         involving DM fractions are caused by two fundamental ones with 
                         galaxy e\ffective radius and central velocity dispersion. 
                         These correlations are independent of each other, so that ETGs 
                         populate a central-DM plane (DMP), i.e. a correlation among 
                         fraction of total-to-stellar mass, e\ffective radius, and 
                         velocity dispersion, whose scatter along the total-to-stellar mass 
                         axis amounts to \∼ 0.15 dex. (3) In general, under the 
                         assumption of an isothermal or a constant M/L pro\file for 
                         the total mass distribution, a Chabrier IMF is favoured with 
                         respect to a bottom-heavier Salpeter IMF, as the latter produces 
                         negative (i.e. unphysical) DM fractions for more than 50% of the 
                         galaxies in our sample. For a Chabrier IMF, the DM estimates agree 
                         with \ΛCDM toy-galaxy models based on contracted DM-halo 
                         density pro\files. We also \find agreement with 
                         predictions from hydrodynamical simulations. (4) The central DM 
                         content of ETGs does not depend signi\ficantly on the 
                         environment where galaxies reside, with group and \field 
                         ETGs having similar DM trends.",
                 issn = "1365-2966",
             language = "en",
        urlaccessdate = "03 maio 2024"
}