2007 ApJL Special Issue

M. Davis et al., "The All-wavelength Extended Groth Strip International Survey (AEGIS) Data Sets"

This lead article of the special issue describes the parameters of the various data sets comprising the AEGIS survey: X-rays, ultraviolet, visible light, infrared, and radio. The sky coverage of the different data sets are illustrated.

C. Conselice et al., "The Diversity of Bright Near-IR Selected Distant Red Galaxies"

Full AEGIS data are brought to bear on a sample of galaxies selected to have red J-K colors. It is shown that this commonly used method for isolating distant non-starforming galaxies in fact returns highly heterogeneous samples that are in general much closer than usually assumed.

T. Fang et al., "Chandra Observations of DEEP2 Galaxy Groups and Clusters"

Distant groups and clusters of galaxies, seen at a time when the Universe was about half its present age, are found to be weaker X-ray emitters than their local counterparts. This is either because galaxies had not yet settled into the cluster/group gravitational potential or because clusters/groups were dificient in hot ionized plams (that fills intergalactic space) in the past.

A. Georgakakis et al., "The Environment of X-ray Sources at z~1"

Chandra X-ray data are used to identify galaxies harboring active galactic nuclei (AGNs) whose black holes are accreting gas. Galaxies with AGNs are located in denser regions of space and have more neighbors than galaxies without AGNs.

B. Gerke et al., "Observations of a Dual AGN at z=0.7"

A distant elliptical-like galaxy is identified that may habor two separate AGNs. The BHs in these AGNs likely came from two separate galaxies that have merged, and the BHs will themselves likely merge in the not-too-distant future.

J.-S. Huang et al., "Infrared Spectroscopy of An Infrared Luminous Lyman Break Galaxy at z=3.01"

This paper announces the first discovery of a distant (z = 3) galaxy with PAH (polycyclic hydrocarbon) emission. The emission is thought to be due to an extremely energetic burst of star formation, the first to be detected at such early times using the PAH indicator.

R.J. Ivison et al., "A Radio Survey of the Extended Groth Strip"

This paper describes the AEGIS20 VLA radio survey at 20 cm wavelengths. The survey detects over 1,000 star-bursting galaxies out to redshift z ~ 1, but the sample also contains many AGN radiating at radio wavelengths. Great care will be needed to separate the two types of objects.

S.A. Kassin et al., "The Stellar Mass Tully-Fisher Relation to z=1.2 from AEGIS"

The Tully-Fisher (TF) relation for nearby galaxies says that more massive disk-like galaxies rotate faster than smaller ones. The correlation between rotation speed and stellar mass is remarkably tight. This paper traces the roots of the TF relation out to z = 1 and beyond, and furthermore shows that more massive galaxies settle to quiescent, stable rotating disks faster than smaller ones.

N. Konidaris et al., "Galaxy Spectral Energy Distributions from the X-ray to the Radio"

This paper presents a first multi-wavelength survey of the broad-band spectral energy distributions (SEDs) of 71 AEGIS galaxies using X-ray through 24 micron data. Broad-band SEDs closely follow optical restframe U-B, which suggests that the galaxies follow smoothly declining star-formation trajectories and that starbursting galaxies are not frequent.

E. LeFloc'h et al., "Far-infrared characterization of an ultra-luminous starburst associated with a massively-accreting black hole at z=1.15"

The paper describes a multi-wavelength study of an X-ray luminous active galactic nucleus located in a merging galaxy at z = 1.15. Roughly 50% of the total luminosity is emitted by a cold dust component associated with a nuclear starburst. The object is an interesting "transition system" with properties that are intermediate between quasars on the one hand and starbursts on the other.

L. Lin et al., "Enhancement of Dust Enshrouded Star Formation in Close Galaxy Pairs and Merging Galaxies up to z~1"

Pairs of galaxies undergoing close gravitational interaction are shown to exhibit elevated levels of dust-enshrouded star formation activity relative to isolated galaxies. The degree of enhancement of star formation is greatest for the closest pairs, but many other factors also appear to be at work.

L.A. Moustakas et al., "A Strong-Lens Survey in AEGIS: the influence of large scale structure"

This paper announces the discovery of a pair of gravitational lens systems. Using Hubble Space Telescope images to study the apparent distortion of the background galaxy images and spectroscopic redshifts from the DEEP2 survey to measure the distances to the lensing and lensed galaxies, the authors are able to constrain the distribution of dark matter in the lensing galaxies.

K. Nandra et al., "The Color-Magnitude Relation for X-ray Selected AGN"

This article studies the colors and luminosities of active galactic nuclei, a type of galaxy that is powered by a massive black hole at its center. The black hole appears to have the effect of terminating active star formation.

K. Noeske et al., "Star formation in field galaxies since z=1.1: Dominance of gradually declining over episodic star formation"

This paper studies the history of star formation in galaxies over more than half the age of the Universe. Galaxies segregate into typical star-forming and non-star-forming systems. The star-forming galaxies form a "main sequence" where galaxies of the same mass have a limited range of star-forming activity. This finding limits the role of brief episodes of intense star formation (starbursts) and show that star formation in galaxies predominantly followed a gradual decline.

K. Noeske et al., "Star formation in AEGIS field galaxies since z=1.1: Staged galaxy formation, and a model of mass-dependent gas exhaustion"

The history of star formation in galaxies can be reproduced by simple models where galaxies gradually exhaust their gas through forming stars, slowing down star formation with time. In this model, less massive galaxeis use up their gas more slowly and start major star formation later than massive galaxies.

C.M. Pierce et al., "Host Galaxy Morphologies of X-ray and Infrared-Selected AGN at 0.2 < z < 1.2"

Using HST ACS images, Chandra X-ray and Spitzter IRAC mid-ID data, and a combination of DEEP2 spectroscopic and CFHTLS photometric redshifts, we identify active galactic nuclei (AGN) and analyze the morphologies and kinematic pairing of their host galaxies. The hosts of X-ray-selected AGN are more likely to have early-type morphologies than the field galaxies, while the hosts of IR-selected AGN have morphologies that are roughly consistent with the field galaxies.

M. Symeonidis et al., "Infrared Spectral Energy Distributions of MIPS 70 micron selected sources"

Optical-infrared spectral energy distributions are used to measure star formation rates in distant galaxies. Template spectra are created that can be used to translate far-IR luminosities into total star formation rates for high-redshift objects.

B. Weiner et al., "Extinction and Star Formation Tracers from Line Emission"

This paper uses DEEP2 spectra, near-IR magnitudes, and Spitzer/MIPS 24 micron fluxes to measure trends in extinction, [OII]/Ha line ratio, and AGN presence with galaxy luminosity and color. There are well-defined trends that affect the use of emission lines as star formation rate indicators, but most of the effects of extinction can be corrected for.

G. Wilson et al., "A Panchromatic Study of IRAC-selected Extremely Red Objects with Confirmed Spectroscopic Redshifts"

The mid-infrared properties of distant very red galaxies are used to reliably classify them into three distinct types: galaxies containing only old stars, dusty galaxies, and galaxies powered by a central massive black hole.

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