%0 Generic %1 newman2015luminous %A Newman, Andrew B. %A Ellis, Richard S. %A Treu, Tommaso %D 2015 %K dark group matter profile %T Luminous and Dark Matter Profiles from Galaxies to Clusters: Bridging the Gap with Group-scale Lenses %U http://arxiv.org/abs/1503.05282 %X Observations of strong gravitational lensing, stellar kinematics, and mass tracers on larger scales enable accurate measures of the distribution of dark matter and baryons in massive early-type galaxies (ETGs). While such techniques have previously been applied to galaxy-scale and cluster-scale lenses, the paucity of intermediate-mass systems with high-quality data has precluded a uniform analysis of mass-dependent trends. With the aim of bridging this gap, we present new observations and analyses of 10 group-scale lenses at <z>=0.36 characterized by Einstein radii 2.5"-5.1" and a mean halo mass of M_200 = 10^14.0 Msol. For these groups, we find a mean halo concentration c_200 = 5.0 +- 0.8 consistent with unmodified cold dark matter halos and recent simulations of galaxy formation. By combining our data with other lens samples in the literature, we analyze the mass structure of ETGs in halos spanning the mass range 10^13-10^15 Msol using homogeneous methods and data. We show that the slope of the total density profile gamma_tot within the effective radius depends on the stellar surface density, as demonstrated previously, but also on the halo mass. We analyze these trends using halo occupation models and resolved stellar kinematics with the goal of testing the universality of the dark matter profile within ETGs of various masses. Whereas the central galaxies of clusters require a shallow inner dark matter density profile, group-scale lenses are consistent with an unmodified Navarro-Frenk-White profile or one that is slightly contracted. We conclude that the net effect of baryons on the dark matter distribution may not be universal, but more likely varies with halo mass due to underlying trends in star formation efficiency and assembly history.

@misc{newman2015luminous, abstract = {Observations of strong gravitational lensing, stellar kinematics, and mass tracers on larger scales enable accurate measures of the distribution of dark matter and baryons in massive early-type galaxies (ETGs). While such techniques have previously been applied to galaxy-scale and cluster-scale lenses, the paucity of intermediate-mass systems with high-quality data has precluded a uniform analysis of mass-dependent trends. With the aim of bridging this gap, we present new observations and analyses of 10 group-scale lenses at <z>=0.36 characterized by Einstein radii 2.5"-5.1" and a mean halo mass of M_200 = 10^14.0 Msol. For these groups, we find a mean halo concentration c_200 = 5.0 +- 0.8 consistent with unmodified cold dark matter halos and recent simulations of galaxy formation. By combining our data with other lens samples in the literature, we analyze the mass structure of ETGs in halos spanning the mass range 10^13-10^15 Msol using homogeneous methods and data. We show that the slope of the total density profile gamma_tot within the effective radius depends on the stellar surface density, as demonstrated previously, but also on the halo mass. We analyze these trends using halo occupation models and resolved stellar kinematics with the goal of testing the universality of the dark matter profile within ETGs of various masses. Whereas the central galaxies of clusters require a shallow inner dark matter density profile, group-scale lenses are consistent with an unmodified Navarro-Frenk-White profile or one that is slightly contracted. We conclude that the net effect of baryons on the dark matter distribution may not be universal, but more likely varies with halo mass due to underlying trends in star formation efficiency and assembly history.}, added-at = {2015-03-19T07:47:02.000+0100}, author = {Newman, Andrew B. and Ellis, Richard S. and Treu, Tommaso}, biburl = {https://www.bibsonomy.org/bibtex/20bad3618d0cb4ca3dde16f95fd56a5c9/miki}, description = {[1503.05282] Luminous and Dark Matter Profiles from Galaxies to Clusters: Bridging the Gap with Group-scale Lenses}, interhash = {6945b4b7391c7e2f9e34a060c1b6393e}, intrahash = {0bad3618d0cb4ca3dde16f95fd56a5c9}, keywords = {dark group matter profile}, note = {cite arxiv:1503.05282Comment: Submitted to ApJ. Comments welcome}, timestamp = {2015-03-19T07:47:02.000+0100}, title = {Luminous and Dark Matter Profiles from Galaxies to Clusters: Bridging the Gap with Group-scale Lenses}, url = {http://arxiv.org/abs/1503.05282}, year = 2015 }