Using Strong Gravitational Lensing to Identify Fossil Group Progenitors

Abstract

Fossil galaxy systems are classically thought to be the end result of galaxy group/cluster evolution, as galaxies experiencing dynamical friction sink to the center of the group potential and merge into a single, giant elliptical that dominates the rest of the members in both mass and luminosity. Most fossil systems discovered lie within $z<0.2$, which leads to the question: what were these systems' progenitors? Such progenitors are expected to have imminent or ongoing major merging near the brightest group galaxy (BGG) that, when concluded, will meet the fossil criteria within the look back time. Since strong gravitational lensing preferentially selects groups merging along the line of sight, or systems with a high mass concentration like fossil systems, we searched the CASSOWARY survey of strong lensing events with the goal of determining if lensing systems have any predisposition to being fossil systems or progenitors. We find that $\sim$13% of lensing groups are identified as traditional fossils while only $\sim$3% of non-lensing control groups are. We also find that $\sim$23% of lensing systems are traditional fossil progenitors compared to $\sim$17% for the control sample. Our findings show that strong lensing systems are more likely to be fossil/pre-fossil systems than comparable non-lensing systems. Cumulative galaxy luminosity functions of the lensing and non-lensing groups also indicate a possible, fundamental difference between strong lensing and non-lensing systems' galaxy populations with lensing systems housing a greater number of bright galaxies even in the outskirts of groups.

arXiv comment14 pages, 6 figures, 2 tables, submitted to ApJ

References in corpus (31)

• Concentrations of Dark Halos from their Assembly Histories
• A Comprehensive Analysis of Uncertainties Affecting the Stellar Mass - Halo Mass Relation for 0<z<4
• A catalog of 132,684 clusters of galaxies identified from Sloan Digital Sky Survey III
• The nature and space density of fossil groups of galaxies
• Analytical approximations of K-corrections in optical and near-infrared bands
• A calibration of the relation between the abundance of close galaxy pairs and the rate of galaxy mergers
• Measurement of Galaxy Cluster Sizes, Radial Profiles, and Luminosity Functions from SDSS Photometric Data
• Robust Optical Richness Estimation with Reduced Scatter
• A cluster finding algorithm based on the multiband identification of red sequence galaxies
• Scaling relations in fossil galaxy groups
• An old galaxy group: Chandra X-ray observations of the nearby fossil group NGC 6482
• The CASSOWARY spectroscopy survey: A new sample of gravitationally lensed galaxies in SDSS
• The Fossil Phase in the Life of a Galaxy Group
• The Ultimate Halo Mass in a LCDM Universe
• The mass assembly of galaxy groups and the evolution of the magnitude gap
• Two New Large Separation Gravitational Lenses from SDSS
• ESO 3060170 -- a massive fossil galaxy group with a heated gas core?
• A fossil galaxy cluster; an X-ray and optical study of RX J1416.4+2315
• Mining the gap: evolution of the magnitude gap in X-ray galaxy groups from the 3 square degree XMM coverage of CFHTLS
• Ultimate age-dating method for galaxy groups; clues from the Millennium Simulations
• NoSOCS in SDSS. II. Mass Calibration of Low Redshift Galaxy Clusters with Optical and X-ray Properties
• Evolution of compact and fossil groups of galaxies from semi-analytical models of galaxy formation
• Do the stellar populations of the brightest two group galaxies depend on the magnitude gap?
• Fossil group origins V. The dependence of the luminosity function on the magnitude gap
• The Sloan Bright Arcs Survey: Ten Strong Gravitational Lensing Clusters and Evidence of Overconcentration
• Empirical optical k-Corrections for redshifts <= 0.7
• Spectral-based k-corrections and implications for the colour-magnitude relation of E/S0s and its evolution
• Fossil groups in the Millennium simulation. From the brightest to the faintest galaxies during the past 8 Gyr
• Measuring the total and baryonic mass profiles of the very massive CASSOWARY 31 strong lens. A fossil system at z ~ 0.7?
• A Normal Abundance of Faint Satellites in the Fossil Group NGC 6482
• How much of the extreme luminosity of IRAS F10214+4724 can be attributed to gravitational lensing

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• Constraining the multi-scale dark-matter distribution in CASSOWARY 31 with strong gravitational lensing and stellar dynamics
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• Cosmography from accurate mass modeling of the lens group SDSS J0100+1818: five sources at three different redshifts
• Chandra and HST Snapshots of Fossil System Progenitors
• Independent Evidence for earlier formation epochs of fossil groups of galaxies through the intracluster light: the case for RX J100742.53+380046.6
• The lens SW05 J143454.4+522850: a fossil group at redshift 0.6?