John A. R. Caldwell

Less than 10 percent of star formation in z=0.6 massive galaxies is triggered by major interactions (2009)

Robaina, Aday R., Bell, Eric F., Skelton, Rosalind E., McIntosh, Daniel H., Somerville, Rachel S., Zheng, Xianzhong, ...

Both observations and simulations show that major tidal interactions or mergers between gas-rich galaxies can lead to intense bursts of starformation. Yet, the average enhancement in star formation...

Optically-passive spirals: The missing link in gradual star formation suppression upon cluster infall (2009)

Wolf, Christian, Aragón-Salamanca, Alfonso, Balogh, Michael, Barden, Marco, Bell, Eric F., Gray, Meghan E., ...

Galaxies migrate from the blue cloud to the red sequence when their star formation is quenched. Here, we report on galaxies quenched by environmental effects and not by mergers or strong AGN as often...

History of Galaxy Interactions and their Impact on Star Formation over the Last 7 Gyr from GEMS (2009)

Jogee, Shardha, Miller, Sarah H., Penner, Kyle, Skelton, Rosalind E., Conselice, Christopher J., Somerville, Rachel S., ...

We perform a comprehensive estimate of the frequency of galaxy mergers and their impact on star formation over z~0.24--0.80 (lookback time T_b~3--7 Gyr) using 3698 (M*>=1e9 Msun) galaxies with GEMS...

The STAGES view of red spirals and dusty red galaxies: Mass-dependent quenching of star-formation in cluster infall (2008)

Wolf, Christian, Aragon-Salamanca, Alfonso, Balogh, Michael, Barden, Marco, Bell, Eric F., Gray, Meghan E., ...

We investigate the properties of optically passive spirals and dusty red galaxies in the A901/2 cluster complex at redshift ~0.17 using restframe near-UV-optical SEDs, 24 micron IR data and HST...

STAGES: the Space Telescope A901/2 Galaxy Evolution Survey (2008)

Gray, M. E., Wolf, Christian, Barden, Marco, Peng, Chien Y., Haeussler, Boris, Bell, Eric F., ...

We present an overview of the Space Telescope A901/2 Galaxy Evolution Survey (STAGES). STAGES is a multiwavelength project designed to probe physical drivers of galaxy evolution across a wide range...

The dark matter environment of the Abell 901/902 supercluster: a weak lensing analysis of the HST STAGES survey (2008)

Heymans, Catherine, Gray, Meghan E., Peng, Chien Y., Van Waerbeke, Ludovic, Bell, Eric F., Wolf, Christian, ...

We present a high resolution dark matter reconstruction of the z=0.165 Abell 901/902 supercluster from a weak lensing analysis of the HST STAGES survey. We detect the four main structures of the...

An explanation for the observed weak size evolution of disk galaxies (2008)

Somerville, Rachel S., Barden, Marco, Rix, Hans-Walter, Bell, Eric F., Beckwith, Steven V. W., Borch, Andrea, ...

Surveys of distant galaxies with the Hubble Space Telescope and from the ground have shown that there is only mild evolution in the relationship between radial size and stellar mass for galactic...

The dark matter environment of the Abell 901/902 supercluster: a weak lensing analysis of the HST STAGES survey (2008)

Heymans, Catherine, Gray, Meghan E., Peng, Chien Y., Van Waerbeke, Ludovic, Bell, Eric F., Wolf, Christian, ...

We present a high-resolution dark matter reconstruction of the z = 0.165 Abell 901/902 supercluster from a weak lensing analysis of the Hubble Space Telescope STAGES survey. We detect the four main...

GEMS survey data and catalog (2008)

Caldwell, John A. R., McIntosh, Daniel H., Rix, Hans-Walter, Barden, Marco, Beckwith, Steven V. W., Bell, Eric F., ...

We describe the data reduction and object cataloging for the GEMS survey, a large-area (800 arcmin2) two-band (F606W and F850LP) imaging survey with the Advanced Camera for Surveys on the Hubble...

GEMS: Galaxy fitting catalogues and testing parametric galaxy fitting codes (2007)

Ler, Boris Häu\ss, McIntosh, Daniel H., Barden, Marco, Bell, Eric F., Rix, Hans-Walter, Borch, Andrea, ...

In the context of measuring structure and morphology of intermediate redshift galaxies with recent HST/ACS surveys, we tune, test, and compare two widely used fitting codes (GALFIT and GIM2D) for...

GEMS: galaxy fitting catalogs and testing parametric galaxy fitting codes: GALFIT and GIM2D (2007)

Häußler, Boris, McIntosh, Daniel H., Barden, Marco, Bell, Eric F., Rix, Hans-Walter, Borch, Andrea, ...

In the context of measuring the structures of intermediate-redshift galaxies with HST ACS surveys, we tune, test, and compare two widely used fitting codes (GALFIT and GIM2D) for fitting...

An Explanation for the Observed Weak Size Evolution of Disk Galaxies (2006)

Somerville, Rachel S., Barden, Marco, Rix, Hans-Walter, Bell, Eric F., Beckwith, Steven V. W., Borch, Andrea, ...

Surveys of distant galaxies with the Hubble Space Telescope and from the ground have shown that there is only mild evolution in the relationship between radial size and stellar mass for galactic...

The Hubble Ultra Deep Field (2006)

Beckwith, Steven V. W., Stiavelli, Massimo, Koekemoer, Anton M., Caldwell, John A. R., Ferguson, Henry C., Hook, Richard, ...

This paper presents the Hubble Ultra Deep Field (HUDF), a one million second exposure of an 11 square minute-of-arc region in the southern sky with the Hubble Space Telescope. The exposure time was...

A weak lensing estimate from GEMS of the virial to stellar mass ratio in massive galaxies to z~0.8 (2006)

Heymans, Catherine, Bell, Eric F., Rix, Hans-Walter, Barden, Marco, Borch, Andrea, Caldwell, John A. R., ...

We present constraints on the evolution of the virial to stellar mass ratio of galaxies with high stellar masses in the redshift range 0.2

Color, Structure, and Star Formation History of Dwarf Galaxies over the last ~3 Gyr with GEMS and SDSS (2006)

Barazza, Fabio D., Jogee, Shardha, Rix, Hans-Walter, Barden, Marco, Bell, Eric F., Caldwell, John A. R., ...

We present a study of the colors, structural properties, and star formation histories for a sample of ~1600 dwarfs over look-back times of ~3 Gyr (z=0.002-0.25). The sample consists of 401 distant...

A weak lensing estimate from GEMS of the virial to stellar mass ratio in massive galaxies to z ~ 0.8 (2006)

Heymans, Catherine, Bell, Eric F., Rix, Hans-Walter, Barden, Marco, Borch, Andrea, Caldwell, John A. R., ...

We present constraints on the evolution of the virial to stellar mass ratio of galaxies with high stellar masses in the redshift range 0.2 < z < 0.8, by comparing weak lensing measurements of virial...

Dry mergers in GEMS: The dynamical evolution of massive early-type galaxies (2006)

Bell, Eric F., Naab, Thorsten, McIntosh, Daniel H., Somerville, Rachel S., Caldwell, John A. R., Barden, Marco, ...

We have used the 28'×28' Hubble Space Telescope image mosaic from the GEMS (Galaxy Evolution from Morphology and SEDs) survey in conjunction with the COMBO-17 photometric redshift survey to...

The Hubble Ultra Deep Field (2006)

Beckwith, Steven V. W., Stiavelli, Massimo, Koekemoer, Anton M., Caldwell, John A. R., Ferguson, Henry C., Hook, Richard, ...

This paper presents the Hubble Ultra Deep Field (HUDF), a 1 million s exposure of an 11 arcmin2 region in the southern sky with the Advanced Camera for Surveys on the Hubble Space Telescope using...

Color, structure, and star formation history of dwarf galaxies over the last ~3 Gyr with GEMS and SDSS (2006)

Barazza, Fabio D., Jogee, Shardha, Rix, Hans-Walter, Barden, Marco, Bell, Eric F., Caldwell, John A. R., ...

We present a study of the colors, structural properties, and star formation histories for a sample of ~1600 dwarfs over look-back times of ~3 Gyr (z=0.002-0.25). The sample consists of 401 distant...

Studying distant dwarf galaxies with GEMS and SDSS (2005)

Barazza, Fabio D., Jogee, Shardha, Rix, Hans-Walter, Barden, Marco, Bell, Eric F., Caldwell, John A. R., ...

We study the colors, structural properties, and star formation histories of a sample of ~1600 dwarfs over look-back times of ~3 Gyr (z=0.002-0.25). The sample consists of 401 distant dwarfs drawn...

Dry Mergers in GEMS: The Dynamical Evolution of Massive Early-Type Galaxies (2005)

Bell, Eric F., Naab, Thorsten, McIntosh, Daniel H., Somerville, Rachel S., Caldwell, John A. R., Barden, Marco, ...

We have used the 28'x 28' HST image mosaic from the GEMS (Galaxy Evolution from Morphology and SEDs) survey in conjunction with the COMBO-17 photometric redshift survey to constrain the incidence of...

GEMS: The Size Evolution of Disk Galaxies (2005)

Barden, Marco, Rix, Hans-Walter, Somerville, Rachel S., Bell, Eric F., Haeussler, Boris, Peng, Chien Y., ...

We combine HST imaging from the GEMS survey with photometric redshifts from COMBO-17 to explore the evolution of disk-dominated galaxies since z

Towards an understanding of the rapid decline of the cosmic star formation rate (2005)

Bell, Eric F., Papovich, Casey, Wolf, Christian, Floc'h, Emeric Le, Caldwell, John A. R., Barden, Marco, ...

We present a first analysis of deep 24 micron observations with the Spitzer Space Telescope of a sample of nearly 1500 galaxies in a thin redshift slice, 0.65

The evolution of early-type red galaxies with the GEMS survey: Luminosity-size and stellar mass-size relations since z=1 (2005)

McIntosh, Daniel H., Bell, Eric F., Rix, Hans-Walter, Wolf, Christian, Heymans, Catherine, Peng, Chien Y., ...

We combine imaging from the Hubble Space Telescope Advanced Camera for Surveys, as part of the GEMS (Galaxy Evolution from Morphologies and SEDs) survey, with redshifts and rest-frame quantities from...

Toward an understanding of the rapid decline of the cosmic star formation rate (2005)

Bell, Eric F., Papovich, Casey, Wolf, Christian, Le Floc'h, Emeric, Caldwell, John A. R., Barden, Marco, ...

We present a first analysis of deep 24 mum observations with the Spitzer Space Telescope of a sample of nearly 1500 galaxies in a thin redshift slice, 0.65

Cosmological weak lensing with the HST GEMS survey (2005)

Heymans, Catherine, Brown, Michael L., Barden, Marco, Caldwell, John A. R., Jahnke, Knud, Peng, Chien Y., ...

We present our cosmic shear analysis of GEMS, one of the largest wide-field surveys ever undertaken by the Hubble Space Telescope. Imaged with the Advanced Camera for Surveys (ACS), GEMS spans 795...

Weak Lensing Results from GEMS (2005)

Heymans, Catherine, Brown, Michael L., Barden, Marco, Caldwell, John A. R., Jahnke, Knud, Rix, Hans-Walter, ...

We present our cosmic shear analysis of the Galaxy Evolution from Morphology and SEDs (GEMS) survey. Imaged with the Advanced Camera for Surveys (ACS) on HST, GEMS provides high resolution imaging...

GEMS: The surface brightness and surface mass density evolution of disk galaxies (2005)

Barden, Marco, Rix, Hans-Walter, Somerville, Rachel S., Bell, Eric F., Häußler, Boris, Peng, Chien Y., ...

We combine HST imaging from the GEMS (Galaxy Evolution from Morphologies and SEDs) survey with photometric redshifts from COMBO-17 to explore the evolution of disk-dominated galaxies since z

The Evolution of Early-type Red Galaxies with the GEMS Survey: Luminosity-size and Stellar Mass-size Relations Since z=1 (2004)

McIntosh, Daniel H., Bell, Eric F., Rix, Hans-Walter, Wolf, Christian, Heymans, Catherine, Peng, Chien Y., ...

We combine HST/ACS imaging from the GEMS survey with redshifts and rest-frame quantities from COMBO-17 to study the evolution of morphologically early-type galaxies with red colors since z=1. We use...

Cosmological weak lensing with the HST GEMS survey (2004)

Heymans, Catherine, Brown, Michael L., Barden, Marco, Caldwell, John A. R., Jahnke, Knud, Peng, Chien Y., ...

We present our cosmic shear analysis of GEMS, one of the largest wide-field surveys ever undertaken by the Hubble Space Telescope. Imaged with the Advanced Camera for Surveys (ACS), GEMS spans 795...

GEMS: Galaxy Evolution from Morphologies and SEDs (2004)

Rix, Hans-Walter, Barden, Marco, Beckwith, Steven V. W., Bell, Eric F., Caldwell, John A. R., Haeussler, Boris, ...

GEMS, Galaxy Evolution from Morphologies and SEDs, is a large-area (800 arcmin2) two-color (F606W and F850LP) imaging survey with the Advanced Camera for Surveys on HST. Centered on the Chandra Deep...

WFI J2026-4536 and WFI J2033-4723: Two new quadruple gravitational lenses (2004)

Morgan, Nicholas D., Caldwell, John A. R., Schechter, Paul L., Dressler, Alan, Egami, Eiichi, Rix, Hans-Walter

We report the discovery of two new gravitationally lensed quasars, WFI J2026-4536 and WFI J2033-4723, at respective source redshifts of z=2.23 and z=1.66. Both systems are quadruply imaged and have...

GEMS: Galaxy evolution from morphologies and SEDs (2004)

Rix, Hans-Walter, Barden, Marco, Beckwith, Steven V. W., Bell, Eric F., Borch, Andrea, Caldwell, John A. R., ...

GEMS (Galaxy Evolution from Morphologies and SEDs) is a large-area (800 arcmin2) two-color (F606W and F850LP) imaging survey with the Advanced Camera for Surveys on the Hubble Space Telescope....

GEMS imaging of red-sequence galaxies at z~0.7: Dusty or old? (2004)

Bell, Eric F., McIntosh, Daniel H., Barden, Marco, Wolf, Christian, Caldwell, John A. R., Rix, Hans-Walter, ...

We have used the 30'‚‚times;30' Hubble Space Telescope image mosaic from the Galaxy Evolution from Morphology and Spectral energy distributions (GEMS) project in conjunction with the COMBO-17 deep...

Bar evolution over the last 8 billion years: A constant fraction of strong bars in the GEMS survey (2004)

Jogee, Shardha, Barazza, Fabio D., Rix, Hans-Walter, Shlosman, Isaac, Barden, Marco, Wolf, Christian, ...

One-third of present-day spirals host optically visible strong bars that drive their dynamical evolution. However, the fundamental question of how bars evolve over cosmological times has yet to be...

Mass Segregation in the Globular Cluster Palomar 5 and its Tidal Tails (2004)

Koch, Andreas, Grebel, Eva K., Odenkirchen, Michael, Martínez-Delgado, David, Caldwell, John A. R.

We present the stellar main-sequence luminosity function (LF) of the disrupted, low-mass, low-concentration globular cluster Palomar 5 and its well-defined tidal tails, which emanate from the cluster...

WFI J2026-4536 and WFI J2033-4723: Two New Quadruple Gravitational Lenses (2003)

Morgan, Nicholas D., Caldwell, John A. R., Schechter, Paul L., Dressler, Alan, Egami, Eiichi, Rix, Hans-Walter

We report the discovery of two new gravitationally lensed quasars, WFI J2026-4536 and WFI J2033-4723, at respective source redshifts of z=2.23 and z=1.66. Both systems are quadruply imaged and have...

GEMS Imaging of Red Sequence Galaxies at z~0.7: Dusty or Old? (2003)

Bell, Eric F., McIntosh, Daniel H., Barden, Marco, Wolf, Christian, Caldwell, John A. R., Rix, Hans-Walter, ...

We have used the 30'x30' Hubble Space Telescope image mosaic from the Galaxy Evolution from Morphology and SEDs (GEMS) project in conjunction with the COMBO-17 deep photometric redshift survey to...

The Shape and Scale of Galactic Rotation from Cepheid Kinematics (1997)

Metzger, Mark R., Caldwell, John A. R., Schechter, Paul L.

A catalog of Cepheid variables is used to probe the kinematics of the Galactic disk. Radial velocities are measured for eight distant Cepheids toward l = 300; these new Cepheids provide a...