SUPERDENSE MASSIVE GALAXIES IN WINGS LOCAL CLUSTERS

By T. Valentinuzzi, J. Fritz, B. Poggianti, A. Cava, D. Bettoni, G. Fasano, M. D’Onofrio, W. Couch, Alan Dressler, M. Molés and 5 more. 2009

134 citations recorded by the source corpus.

Massive quiescent galaxies at z > 1 have been found to have small physical sizes, and hence to be superdense. Several mechanisms, including minor mergers, have been proposed for increasing galaxy sizes from high- to low-z. We search for superdense massive galaxies in the WIde-field Nearby Galaxy-cluster Survey (WINGS) of X-ray selected galaxy clusters at 0.04 < z < 0.07. We discover a significant population of superdense massive galaxies with masses and sizes comparable to those observed at high redshift. They approximately represent 22% of all cluster galaxies more massive than 3 × 1010 M☉, are mostly S0 galaxies, have a median effective radius 〈Re〉 = 1.61 ± 0.29 kpc, a median Sersic index 〈n〉 = 3.0 ± 0.6, and very old stellar populations with a median mass-weighted age of 12.1 ± 1.3 Gyr. We calculate a number density of 2.9 × 10−2 Mpc−3 for superdense galaxies in local clusters, and a hard lower limit of 1.3 × 10−5 Mpc−3 in the whole comoving volume between z = 0.04 and z = 0.07. We find a relation between mass, effective radius, and luminosity-weighted age in our cluster galaxies, which can mimic the claimed evolution of the radius with redshift, if not properly taken into account. We compare our data with spectroscopic high-z surveys and find that—when stellar masses are considered—there is consistency with the local WINGS galaxy sizes out to z ∼ 2, while a discrepancy of a factor of 3 exists with the only spectroscopic z > 2 study. In contrast, there is strong evidence for a large evolution in radius for the most massive galaxies with M* > 4 × 1011 M☉ compared to similarly massive galaxies in WINGS, i.e., the brightest cluster galaxies.

Subfields: Astronomy and Astrophysics, Instrumentation

View Paper: https://www.semanticscholar.org/paper/cdff097da9bb3f2bd98a72d610cde495938fc7b4

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In Astronomy and Astrophysics

1. M. Cappellari
2. T. Naab
3. M. Sarzi
4. P. Hopkins
5. L. Hernquist
6. Roger Davies
7. Eric Emsellem
8. M. Bureau

In Instrumentation

1. M. Cappellari
2. T. Naab
3. M. Sarzi
4. M. Bureau
5. Eric Emsellem
6. P. de Zeeuw
7. D. Krajnovi'c
8. Roger Davies

Citations in the corpus

• The ATLAS3D project – XX. Mass–size and mass–σ distributions of early-type galaxies: bulge fraction drives kinematics, mass-to-light ratio, molecular gas fraction and stellar initial mass function (2012, result): “The age–size trend was also confirmed in different samples of nearby galaxies by Valentinuzzi et al. (2010) and Napolitano, Romanowsky & Tortora (2010), and a similar trend, with star-forming galaxies being larger than passive ones was found in place from redshift z ∼ 2.5 (Williams et al. 2010b;…”
• The sizes, masses and specific star formation rates of massive galaxies at 1.3 < z < 1.5: strong evidence in favour of evolution via minor mergers (2012, background): “For example, it has been claimed that the number densities of compact ETGs at high redshift are actually compatible with compact cluster galaxies seen locally (Valentinuzzi et al. 2010), although this has been disputed by Taylor et al. (2010).”
• Dissecting the size evolution of elliptical galaxies since z∼ 1: puffing-up versus minor-merging scenarios (2011, methodology): “Secondly, the near absence of compact massive galaxies in the nearby Universe (Trujillo et al. 2009; Taylor et al. 2010; Valentinuzzi et al. 2010), which were very common in the early Universe, indicates that individual objects (at least the very old and compact ones) have evolved significantly in…”
• The ATLAS3D project – I. A volume-limited sample of 260 nearby early-type galaxies: science goals and selection criteria (2010, background): “While a trend involving age was presented by van der Wel et al. (2009) and Shankar & Bernardi (2009), and confirmed by Valentinuzzi et al. (2010), who find smaller sizes for older objects, at given stellar mass.”
• 3D-HST+CANDELS: THE EVOLUTION OF THE GALAXY SIZE–MASS DISTRIBUTION SINCE z = 3 (2014, unknown): “…galaxies (with sizes R eff 2kpc) exists within present-day clusters, with a number density comparable to that of higher-redshift early-type galaxies (Valentinuzzi et al. 2010; Poggianti et al. 2013); tension with the absence of such galaxies in the Sloan Digital Sky Survey (SDSS) remains (Trujillo…”
• SUPERDENSE GALAXIES AND THE MASS–SIZE RELATION AT LOW REDSHIFT (2012, methodology): “The existence of a trend of size with age at fixed mass is however still debated (e.g. cf. Valentinuzzi et al. 2010 and Trujillo et al. 2012).”