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Galaxy assembly bias on the red sequence

M. C. Cooper et al. 0 Department of Physics and Astronomy, University of Pittsburgh , 401-C Allen Hall, 3941 O'Hara Street, Pittsburgh, PA 15260, USA 1 Max-Planck-Institut fur Astronomie , Konigstuhl

The Arizona CDFS Environment Survey (ACES): A Magellan/IMACS Spectroscopic Survey of the Chandra Deep Field-South⋆

We present the Arizona CDFS Environment Survey (ACES), a recently completed spectroscopic redshift survey of the Chandra Deep Field-South (CDFS) conducted using the Inamori-Magellan Areal Camera and Spectrograph on the Magellan-Baade telescope. In total, the survey targeted 7277 unique sources down to a limiting magnitude of RAB = 24.1, yielding 5080 secure redshifts across the ∼30 ...

Automated morphological classification of Sloan Digital Sky Survey red sequence galaxies

In the last decade, the advent of enormous galaxy surveys has motivated the development of automated morphological classification schemes to deal with large data volumes. Existing automated schemes can successfully distinguish between early- and late-type galaxies and identify merger candidates, but are inadequate for studying detailed morphologies of red sequence galaxies. To fill ...

Dependence of galaxy quenching on halo mass and distance from its centre

We study the dependence of star formation quenching on galaxy mass and environment, in the Sloan Digital Sky Survey (SDSS; z ∼ 0.1) and the All-Wavelength Extended Groth Strip International Survey (AEGIS; z ∼ 1). It is crucial that we define quenching by low star formation rate rather than by red colour, given that one-third of the red galaxies are star forming. We address stellar ...

How does galaxy environment matter? The relationship between galaxy environments, colour and stellar mass at 0.4 < z < 1 in the Palomar/DEEP2 survey

We present a study characterizing the environments of galaxies in the redshift range of 0.4 < z < 1 based on data from the POWIR near-infrared imaging and DEEP2 spectroscopic redshift surveys, down to a stellar mass of log M*= 10.25 M⊙. Galaxy environments are measured in terms of nearest-neighbour densities as well as fixed aperture densities and kinematical and dynamical ...

Observational constraints on the physics behind the evolution of active galactic nuclei since z∼ 1

We explore the evolution with redshift of the rest-frame colours and space densities of active galactic nuclei (AGN) hosts (relative to normal galaxies) to shed light on the dominant mechanism that triggers accretion on to supermassive black holes as a function of cosmic time. Data from serendipitous wide-area XMM surveys of the Sloan Digital Sky Survey (SDSS) footprint (XMM/SDSS; ...

The role of environment in the mass–metallicity relation

Using a sample of 57 377 star-forming galaxies drawn from the Sloan Digital Sky Survey, we study the relationship between gas-phase oxygen abundance and environment in the local Universe. We find that there is a strong relationship between metallicity and environment such that more metal-rich galaxies favour regions of higher overdensity. Furthermore, this metallicity–density ...

The DEEP3 Galaxy Redshift Survey: the impact of environment on the size evolution of massive early-type galaxies at intermediate redshift*,†

Using data drawn from the DEEP2 and DEEP3 Galaxy Redshift Surveys, we investigate the relationship between the environment and the structure of galaxies residing on the red sequence at intermediate redshift. Within the massive (10 < log10(M★/h−2 M⊙) < 11) early-type population at 0.4 < z < 1.2, we find a significant correlation between local galaxy overdensity (or environment) and ...

Strong size evolution of the most massive galaxies since z ∼ 2

Using the combined capabilities of the large near-infrared Palomar/DEEP-2 survey, and the superb resolution of the Advanced Camera for Surveys HST camera, we explore the size evolution of 831 very massive galaxies (M⋆≥ 1011h−270 M⊙) since z∼ 2. We split our sample according to their light concentration using the Sérsic index n. At a given stellar mass, both low (n 2.5) concentrated ...

X-ray selected AGN in groups at redshifts z≈ 1

We explore the role of the group environment in the evolution of active galactic nuclei (AGN) at the redshift interval 0.7 < z < 1.4, by combining deep Chandra observations with extensive optical spectroscopy from the All-wavelength Extended Groth strip International Survey (AEGIS). The sample consists of 3902 optical sources and 71 X-ray AGN. Compared to the overall optically ...

Groups of galaxies in AEGIS: the 200-ks Chandra extended X-ray source catalogue

We present the discovery of seven X-ray emitting groups of galaxies selected as extended X-ray sources in the 200-ks Chandra coverage of the All-wavelength Extended Groth Strip International Survey (AEGIS). In addition, we report on active galactic nucleus (AGN) activity associated with these systems. For the six extended sources which lie within the Deep Extragalactic Evolutionary ...

The DEEP2 Galaxy Redshift Survey: environments of post-starburst galaxies at z∼ 0.1 and ∼0.8

Post-starburst (also known as K+A) galaxies exhibit spectroscopic signatures indicating that their star formation was recently quenched; they are candidates for galaxies in transition from a star-forming phase to a passively evolving phase. We have spectroscopically identified large samples of post-starburst galaxies both in the Sloan Digital Sky Survey (SDSS) at z∼ 0.1 and in the ...

On the evolution of the velocity–mass–size relations of disc-dominated galaxies over the past 10 billion years

We study the evolution of the scaling relations between the maximum circular velocity, stellar mass and optical half-light radius of star-forming disc-dominated galaxies in the context of Λ cold dark matter-based galaxy formation models. Using data from the literature combined with new data from the Deep Extragalactic Evolutionary Probe 2 (DEEP2) and All-wavelength Extended Groth ...

Host galaxy morphologies of X-ray selected AGN: assessing the significance of different black hole fuelling mechanisms to the accretion density of the Universe at z∼ 1.

We use morphological information of X-ray selected active galactic nuclei (AGN) hosts to set limits on the fraction of the accretion density of the Universe at z≈ 1 that is not likely to be associated with major mergers. Deep X-ray observations are combined with high-resolution optical data from the Hubble Space Telescope in the All-wavelength Extended Groth strip International ...

The DEEP2 Galaxy Redshift Survey: the red sequence AGN fraction and its environment and redshift dependence

We measure the dependence of the active galactic nuclei (AGN) fraction on local environment at z∼ 1, using spectroscopic data taken from the DEEP2 Galaxy Redshift Survey, and Chandra X-ray data from the All-Wavelength Extended Groth Strip International Survey (AEGIS). To provide a clean sample of AGN, we restrict our analysis to the red sequence population; this also reduces ...

Oxford SWIFT integral field spectrograph and multiwavelength observations of the Eagle galaxy at z= 0.77

Michael C. Cooper 8 Jeffrey A. Newman 13 Kevin Bundy 12 C. J. Conselice 7 A. M. Koekemoer 2 Lihwai Lin 3 Leonidas A. Moustakas 4 Tao Wang 1 0 Present address: Astrophysics Science Division, Goddard Space

Extragalactic background light inferred from AEGIS galaxy-SED-type fractions

. Davis 14 P. Guhathakurta 13 P. Barmby 9 C. J. Conselice 4 M. Lozano 8 J. A. Newman 5 M. C. Cooper 3 0 Visiting Student at the Santa Cruz Institute for Particle Physics (SCIPP), University of California

Absence of evidence is not evidence of absence: the colour–density relation at fixed stellar mass persists to z∼ 1*

M. C. Cooper et al. E-mail: 0 0 Some of the data presented herein were obtained at the W. M. Keck Ob- servatory, which is operated as a scientific partnership among the California Institute of

A study of the gas–star formation relation over cosmic time*

We use the first systematic data sets of CO molecular line emission in z∼ 1–3 normal star-forming galaxies (SFGs) for a comparison of the dependence of galaxy-averaged star formation rates on molecular gas masses at low and high redshifts, and in different galactic environments. Although the current high-z samples are still small and biased towards the luminous and massive tail of ...

The role of AGN in the colour transformation of galaxies at redshifts z≈ 1

We explore the role of active galactic nuclei (AGN) in establishing and/or maintaining the bimodal colour distribution of galaxies by quenching their star formation and hence, causing their transition from the blue to the red cloud. Important tests for this scenario include (i) the X-ray properties of galaxies in the transition zone between the two clouds and (ii) the incidence of ...