Mark Lacy

On the 10-micron silicate feature in Active Galactic Nuclei (2009)

Nikutta, Robert, Elitzur, Moshe, Lacy, Mark

The 10-micron silicate feature observed with Spitzer in active galactic nuclei (AGN) reveals some puzzling behavior. It (1) has been detected in emission in type 2 sources, (2) shows broad,...

An Infrared Comparison of Type-1 and Type-2 Quasars (2009)

Hiner, Kyle D., Canalizo, Gabriela, Lacy, Mark, Sajina, Anna, Armus, Lee, Ridgway, Susan, ...

We model the optical to far-infrared SEDs of a sample of six type-1 and six type-2 quasars selected in the mid-infrared. The objects in our sample are matched in mid-IR luminosity and selected based...

Millimetre observations of a sample of high-redshift obscured quasars (2009)

Martinez-Sansigre, Alejo, Karim, Alexander, Schinnerer, Eva, Omont, Alain, Smith, Daniel J. B., Wu, Jingwen, ...

We present observations at 1.2 mm with MAMBO-II of a sample of z>~2 radio-intermediate obscured quasars, as well as CO observations of two sources with the Plateau de Bure Interferometer. Five out of...

The Contribution of High Redshift Galaxies to Cosmic Reionization: New Results from Deep WFC3 Imaging of the Hubble Ultra Deep Field (2009)

Bunker, Andrew, Wilkins, Stephen, Ellis, Richard, Stark, Daniel, Lorenzoni, Silvio, Chiu, Kuenley, ...

We have searched for star-forming galaxies at z~7 by applying the Lyman-break technique to newly-released 1.1micron Y-band images from WFC3 on HST. By comparing these images of the Hubble Ultra Deep...

Galaxies at High Redshift and Reionization (2009)

Bunker, Andrew, Stanway, Elizabeth, Ellis, Richard, Lacy, Mark, McMahon, Richard, Eyles, Laurence, ...

The quest to discover the most distant galaxies has developed rapidly in the last decade. We are now exploring redshifts of 6 and beyond, when the Universe was less than a billion years old, an epoch...

The FIRST-2MASS Red Quasar Survey. II. An Anomalously High Fraction of LoBALs in Searches for Dust-Reddened Quasars (2009)

Urrutia, Tanya, Becker, Robert H., White, Richard L., Glikman, Eilat, Lacy, Mark, Hodge, Jacqueline, ...

We present results on a survey to find extremely dust-reddened Type 1 quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a...

Spectroscopic Confirmation of a Massive Red-Sequence-Selected Galaxy Cluster at z = 1.34 in the SpARCS-South Cluster Survey (2009)

Wilson, Gillian, Muzzin, Adam, Yee, H. K. C., Lacy, Mark, Surace, Jason, Gilbank, David, ...

The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a z'-passband imaging survey, consisting of deep (z' ≃ 24 AB) observations made from both hemispheres using the CFHT 3.6 m and...

Spectroscopic Confirmation of Two Massive Red-Sequence-Selected Galaxy Clusters at z ~ 1.2 in the SpARCS-North Cluster Survey (2009)

Muzzin, Adam, Wilson, Gillian, Yee, H. K. C., Hoekstra, Henk, Gilbank, David, Surace, Jason, ...

The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a deep z'-band imaging survey covering the Spitzer Wide-Area Infrared Extragalactic Survey (SWIRE) Legacy fields designed to...

The Evolutionary History of Lyman Break Galaxies Between Redshift 4 and 6: Observing Successive Generations of Massive Galaxies in Formation (2009)

Stark, Daniel P., Ellis, Richard S., Bunker, Andrew, Bundy, Kevin, Targett, Tom, Benson, Andrew, ...

We present new measurements of the evolution in the Lyman break galaxy (LBG) population between z ≃ 4 and z ≃ 6. By utilizing the extensive multiwavelength data sets available in the GOODS...

Eight-dimensional mid-infrared/optical Bayesian quasar selection (2009)

Richards, Gordon T., Deo, Rajesh P., Lacy, Mark, Myers, Adam D., Nichol, Robert C., Zakamska, Nadia L., ...

We explore the multidimensional, multiwavelength selection of quasars from mid-infrared (MIR) plus optical data, specifically from Spitzer-Infrared Array Camera (IRAC) and the Sloan Digital Sky...

The Evolutionary History of Lyman Break Galaxies Between Redshift 4 and 6: Observing Successive Generations of Massive Galaxies in Formation (2009)

Stark, Daniel P., Ellis, Richard S., Bunker, Andrew, Bundy, Kevin, Targett, Tom, Benson, Andrew, ...

We present new measurements of the evolution in the Lyman break galaxy (LBG) population between z~4 and z~6. By utilizing the extensive multiwavelength datasets available in the GOODS fields, we...

Photometry using the Infrared Array Camera on the Spitzer Space Telescope (2008)

Hora, Joseph L., Carey, Sean, Surace, Jason, Marengo, Massimo, Lowrance, Patrick, Glaccum, William J., ...

We present several corrections for point-source photometry to be applied to data from the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. These corrections are necessary because of...

Eight-Dimensional Mid-Infrared/Optical Bayesian Quasar Selection (2008)

Richards, Gordon T., Deo, Rajesh P., Lacy, Mark, Myers, Adam D., Nichol, Robert C., Zakamska, Nadia L., ...

We explore the multidimensional, multiwavelength selection of quasars from mid-IR (MIR) plus optical data, specifically from Spitzer-IRAC and the Sloan Digital Sky Survey (SDSS). We apply modern...

The Evolution of Dusty Star Formation and Stellar Mass Assembly in Clusters: Results from the IRAC 3.6, 4.5, 5.8, and 8.0 μm Cluster Luminosity Functions (2008)

Muzzin, Adam, Wilson, Gillian, Lacy, Mark, Yee, H. K. C., Stanford, S. A.

We present a catalog of 99 candidate clusters and groups of galaxies in the redshift range 0.1 < z_(phot) < 1.3 discovered in the Spitzer FLS. The clusters are selected by their R_c − 3.6 μm...

Quasar Black Hole Masses from Velocity Dispersions (2008)

Canalizo, Gabriela, Wold, Margrethe, Lazarova, Mariana, Lacy, Mark

Much progress has been made in measuring black hole (BH) masses in (non-active) galactic nuclei using the tight correlation between stellar velocity dispersions sigma in galaxies and the mass of...

Spectroscopic Confirmation of Two Massive Red-Sequence-Selected Galaxy Clusters at z ~ 1.2 in the SpARCS-North Cluster Survey (2008)

Muzzin, Adam, Wilson, Gillian, Yee, H. K. C., Hoekstra, Henk, Gilbank, David, Surace, Jason, ...

The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a deep z'-band imaging survey covering the Spitzer SWIRE Legacy fields designed to create the first large homogeneously-selected...

Spectroscopic Confirmation of a Massive Red-Sequence-Selected Galaxy Cluster at z = 1.34 in the SpARCS-South Cluster Survey (2008)

Wilson, Gillian, Muzzin, Adam, Yee, H. K. C., Lacy, Mark, Surace, Jason, Gilbank, David, ...

The Spitzer Adaptation of the Red-sequence Cluster Survey (SpARCS) is a z'-passband imaging survey, consisting of deep (z' ~ 24 AB) observations made from both hemispheres using the CFHT 3.6m and...

Photometry using the Infrared Array Camera on the Spitzer Space Telescope (2008)

Hora, Joseph L., Carey, Sean, Surace, Jason, Marengo, Massimo, Lowrance, Patrick, Glaccum, William J., ...

We present several corrections for point source photometry to be applied to data from the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. These corrections are necessary because of...

Infrared and millimetre-wavelength evidence for cold accretion within a z=2.83 Lyman α blob (2008)

Smith, Daniel J. B., Jarvis, Matt J., Lacy, Mark, Martínez-Sansigre, Alejo

This paper discusses infrared and millimetre-wavelength observations of a Lyman α blob (LAB) discovered by Smith & Jarvis, a candidate for ionization by the cold accretion scenario discussed in...

The FIRST-2MASS Red Quasar Survey II: An anomalously high fraction of LoBALs in searches for dust-reddened quasars (2008)

Urrutia, Tanya, Becker, Robert H., White, Richard L., Glikman, Eilat, Lacy, Mark, Hodge, Jacqueline, ...

We present results on a survey to find extremely dust-reddened Type-1 Quasars. Combining the FIRST radio survey, the 2MASS Infrared Survey and the Sloan Digital Sky Survey, we have selected a...

Fueling QSOs: The Relevance of Mergers (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

To study the relevance of mergers for the fueling of QSOs, we are currently conducting an HST imaging campaign of a sample of QSO host galaxies classified as ellipticals in the literature. Here, we...

Quasar Black Hole Masses from Velocity Dispersions (2008)

Canalizo, Gabriela, Wold, Margrethe, Lazarova, Mariana, Lacy, Mark

Much progress has been made in measuring black hole (BH) masses in (non-active) galactic nuclei using the tight correlation between stellar velocity dispersions (sigma) in galaxies and the mass of...

The Evolution of Dusty Star Formation and Stellar Mass Assembly in Clusters: Results from the IRAC 3.6um, 4.5um, 5.8um and 8.0um Cluster Luminosity Functions (2008)

Muzzin, Adam, Wilson, Gillian, Lacy, Mark, Yee, H. K. C., Stanford, S. A.

We present a catalogue of 99 candidate clusters and groups of galaxies in the redshift range 0.1 < z_{phot} < 1.3 discovered in the Spitzer First Look Survey (FLS). The clusters are selected by their...

Infrared and millimetre-wavelength evidence for cold accretion within a z = 2.83 Lyman-alpha blob (2008)

Smith, Daniel J. B., Jarvis, Matt J., Lacy, Mark, Martínez-Sansigre, Alejo

This paper discusses infrared and millimetre-wavelength observations of a Lyman-alpha blob discovered by Smith & Jarvis, a candidate for ionization by the cold accretion scenario discussed in Fardal...

Evidence for merger remnants in early-type host galaxies of low-redshift QSOs (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

We present results from a pilot HSTACS deep imaging study in broadband Vof five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine...

Mid-infrared spectroscopy of high-redshift obscured quasars (2008)

Martínez-Sansigre, Alejo, Lacy, Mark, Sajina, Anna, Rawlings, Steve

We present mid-infrared observations of 18 sources from a sample of 21 z ~ 2 radio-intermediate obscured (type 2) quasars. The mid-infrared spectra of the sources are continuum dominated, and 12...

Evidence for quasar activity triggered by galaxy mergers in HST observations of dust-reddened quasars (2008)

Urrutia, Tanya, Lacy, Mark, Becker, Robert H.

We present Hubble Space Telescope ACS images of 13 dust-reddened type 1 quasars selected from the FIRST/2MASS Red Quasar Survey. These quasars have high intrinsic luminosities after correction for...

Evidence for Merger Remnants in Early-Type Host Galaxies of Low-Redshift QSOs (2008)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien Y., ...

We present results from a pilot HST ACS deep imaging study in broad-band V of five low-redshift QSO host galaxies classified in the literature as ellipticals. The aim of our study is to determine...

Infrared and millimetre-wavelength evidence for cold accretion within a z = 2.83 Lyman α blob (2008)

Smith, Daniel J. B., Jarvis, Matt J., Lacy, Mark, Martí­nez-Sansigre, Alejo

This paper discusses infrared and millimetre-wavelength observations of a Lyman alpha blob (LAB) discovered by Smith & Jarvis, a candidate for ionization by the cold accretion scenario discussed in...

Mid-infrared spectroscopy of high-redshift obscured quasars (2008)

Martínez-Sansigre, Alejo, Lacy, Mark, Sajina, Anna, Rawlings, Steve

We present mid-infrared observations of 18 sources from a sample of 21 z~2 radio-intermediate obscured (type 2) quasars. The mid-infrared spectra of the sources are continuum dominated, and 12...

Accepted by ApJS Preprint typeset using L A T E X style emulateapj v. 19/02/01 THE FIRST BRIGHT QUASAR SURVEY III. THE SOUTH GALACTIC CAP 1 (2007)

Robert H. Becker, Richard L. White, Michael S. Brotherton, Chris D. Impey, Frederic H. Chaffee, ...

We present the results of an extension of the FIRST Bright Quasar Survey (FBQS) to the South Galactic cap, and to a fainter optical magnitude limit. Radio source counterparts with SERC R magnitudes...

Spectacular shells in the host galaxy of the QSO MC2 1635+119 (2007)

Canalizo, Gabriela, Bennert, Nicola, Jungwiert, Bruno, Stockton, Alan, Schweizer, François, Lacy, Mark, ...

We present deep HST ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical galaxy. Our new images reveal dramatic shell...

Mid-infrared spectroscopy of high-redshift obscured quasars (2007)

Martinez-Sansigre, Alejo, Lacy, Mark, Sajina, Anna, Rawlings, Steve

We present mid-infrared observations of 18 sources from a sample of 21 z~2 radio-intermediate obscured quasars. The mid-infrared spectra of the sources are continuum dominated, and 12 sources show...

Searching for Mergers in Early-Type QSO Host Galaxies and a Control Sample of Inactive Ellipticals (2007)

Bennert, Nicola, Canalizo, Gabriela, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Peng, Chien, ...

We present very deep HST/ACS images of five QSO host galaxies, classified as undisturbed ellipticals in earlier studies. For four of the five objects, our images reveal strong signs of interaction...

Evidence for Quasar Activity Triggered by Galaxy Mergers in HST Observations of Dust-reddened Quasars (2007)

Urrutia, Tanya, Lacy, Mark, Becker, Robert H.

We present Hubble ACS images of thirteen dust reddened Type-1 quasars selected from the FIRST/2MASS Red Quasar Survey. These quasars have high intrinsic luminosities after correction for dust...

Discovery of Radio Jets in z~2 ULIRGs with Deep 9.7um Silicate Absorption (2007)

Sajina, Anna, Yan, Lin, Lacy, Mark, Huynh, Minh

Recent Spitzer observations have revealed a substantial population of z~2 ULIRGs with deep silicate absorption (\tau_{9.7}>1). This paper reports a 20cm radio study of such a sample to elucidate...

Spectacular Shells in the Host Galaxy of the QSO MC2 1635+119 (2007)

Canalizo, Gabriela, Bennert, Nicola, Jungwiert, Bruno, Stockton, Alan, Schweizer, Francois, Lacy, Mark, ...

We present deep HST/ACS images and Keck spectroscopy of MC2 1635+119, a QSO hosted by a galaxy previously classified as an undisturbed elliptical. Our new images reveal dramatic shell structure...

The FIRST-2MASS Red Quasar Survey (2007)

Glikman, Eilat, Helfand, David J., White, Richard L., Becker, Robert H., Gregg, Michael D., Lacy, Mark

Combining radio observations with optical and infrared color selection -- demonstrated in our pilot study to be an efficient selection algorithm for finding red quasars -- we have obtained optical...

Metal-Enriched Gaseous Halos around Distant Radio Galaxies: Clues to Feedback in Galaxy Formation (2007)

Reuland, Michiel, Van Breugel, Wil, De Vries, Wim, Dopita, Michael A., Dey, Arjun, Miley, George, ...

We present the results of an optical and near-IR spectroscopic study of giant nebular emission-line halos associated with three z > 3 radio galaxies, 4C 41.17, 4C 60.07, and B2 0902+34. Previous deep...

Evidence that FeLoBALs may signify the transition between an ultraluminous infrared galaxy and a quasar (2007)

Farrah, Duncan, Lacy, Mark, Priddey, Robert, Borys, Colin, Afonso, Jose

We present mid/far-infrared photometry of nine FeLoBAL QSOs, taken using the Spitzer space telescope. All nine objects are extremely bright in the infrared, with rest-frame 1-1000 micron luminosities...

The Massive Hosts of Radio Galaxies Across Cosmic Time (2007)

Seymour, Nick, Stern, Daniel, De Breuck, Carlos, Vernet, Joel, Rettura, Alessandro, Dickinson, Mark, ...

We present the results of a comprehensive Spitzer survey of 69 radio galaxies across 1

Metal enriched gaseous halos around distant radio galaxies: Clues to feedback in galaxy formation (2007)

Reuland, Michiel, Van Breugel, Wil, De Vries, Wim, Dopita, Michael A., Dey, Arjun, Miley, George, ...

We present the results of an optical and near-IR spectroscopic study of giant nebular emission line halos associated with three z > 3 radio galaxies, 4C 41.17, 4C 60.07 and B2 0902+34. Previous deep...

The stellar mass density at z ~6 from Spitzer imaging of i'-drop galaxies (2007)

Eyles, Laurence P., Bunker, Andrew J., Ellis, Richard S., Lacy, Mark, Stanway, Elizabeth R., Stark, Daniel P., ...

We measure the ages, stellar masses, and star formation histories of z ~6 galaxies, observed within 1 Gyr of the big bang. We use imaging from the Hubble Space Telescope (HST) and the Spitzer Space...

XMM-Newton detection of the rare Fanaroff-Riley type II broad absorption line quasar first J101614.3+520916 (2006)

Schaefer, Justin J., Brotherton, Michael S., Shang, Zhaohui, Gregg, Michael D., Becker, Robert H., Laurent-Muehleisen, Sally A., ...

We have detected FIRST J101614.3+520916 with the XMM-Newton X-ray observatory. FIRST J101614.3+520916, one of the most extreme radio-loud, broad absorption line (BAL) quasars so far discovered, is...

A population of high-redshift type 2 quasars – I. Selection criteria and optical spectra (2006)

Martínez-Sansigre, Alejo, Rawlings, Steve, Lacy, Mark, Fadda, Dario, Jarvis, Matt J., Marleau, Francine R., ...

We discuss the relative merits of mid-infrared and X-ray selection of type 2 quasars. We describe the mid-infrared, near-infrared and radio selection criteria used to find a population of redshift...

The Stellar Mass Density at z~6 from Spitzer Imaging of i-drop Galaxies (2006)

Eyles, Laurence, Bunker, Andrew, Ellis, Richard, Lacy, Mark, Stanway, Elizabeth, Stark, Daniel, ...

We measure the ages, stellar masses, and star formation histories of z~6 galaxies, observed within 1Gyr of the Big Bang. We use imaging from HST and Spitzer from the public "Great Observatories...

XMM-Newton Detection of the Rare FR II BAL Quasar FIRST J101614.3+520916 (2006)

Schaefer, Justin J., Brotherton, Michael S., Shang, Zhaohui, Gregg, Michael D., Becker, Robert H., Laurent-Muehleisen, Sally A., ...

We have detected FIRST J101614.3+520916 with the XMM-Newton X-ray Observatory. FIRST J101614.3+520916, one of the most extreme radio-loud, broad absorption line (BAL) quasars so far discovered, is...

A population of high-redshift type-2 quasars-I. Selection Criteria and Optical Spectra (2006)

Martinez-Sansigre, Alejo, Rawlings, Steve, Lacy, Mark, Fadda, Dario, Jarvis, Matt J., Marleau, Francine R., ...

We discuss the relative merits of mid-infrared and X-ray selection of type-2 quasars. We describe the mid-infrared, near-infrared and radio selection criteria used to find a population of redshift...

Clusters of Galaxies at 1 < z < 2 : The Spitzer Adaptation of the Red-Sequence Cluster Survey (2006)

Wilson, Gillian, Muzzin, Adam, Lacy, Mark, Yee, Howard, Surace, Jason, Lonsdale, Carol, ...

As the densest galaxy environments in the universe, clusters are vital to our understanding of the role that environment plays in galaxy formation and evolution. Unfortunately, the evolution of...

Star Formation in QSO Host Galaxies (2006)

Canalizo, Gabriela, Stockton, Alan, Brotherton, Michael S., Lacy, Mark

Many of the conditions that are necessary for starbursts appear to be important in the triggering of QSOs. However, it is still debatable whether starbursts are ubiquitously present in galaxies...

Spectral Energy Distributions and Multiwavelength Selection of Type 1 Quasars (2006)

Richards, Gordon T., Lacy, Mark, Storrie-Lombardi, Lisa J., Hall, Patrick B., Gallagher, S. C., Hines, Dean C., ...

We present an analysis of the mid-infrared (MIR) and optical properties of type 1 (broad-line) quasars detected by the Spitzer Space Telescope. The MIR color-redshift relation is characterized to...

Quasars and their host galaxies (2006)

Lacy, Mark

This review attempts to describe developments in the fields of quasar and quasar host galaxies in the past five. In this time period, the Sloan and 2dF quasar surveys have added several tens of...

Spectral energy distributions and multiwavelength selection of type 1 quasars (2006)

Richards, Gordon T., Lacy, Mark, Storrie-Lombardi, Lisa J., Hall, Patrick B., Gallagher, S. C., Hines, Dean C., ...

We present an analysis of the mid-infrared (MIR) and optical properties of type 1 (broad-line) quasars detected by the Spitzer Space Telescope. The MIR color-redshift relation is characterized to...

A population of high-redshift type-2 quasars-I. Selection Criteria and Optical Spectra (2006)

Alejo Martínez-sansigre, Steve Rawlings, Mark Lacy, Dario Fadda, Matt J. Jarvis, Francine R. Marleau, ...

For a long time, a population of obscured (type-2) radioquiet quasars has been postulated from modelling the hard (energies � 1 keV) X-ray background as the sum of the emission from extragalactic...

Most supermassive black hole growth is obscured by dust (2005)

Martinez-Sansigre, Alejo, Rawlings, Steve, Lacy, Mark, Fadda, Dario, Marleau, Francine R., Simpson, Chris, ...

We present an alternative method to X-ray surveys for hunting down the high-redshift type-2 quasar population, using Spitzer and VLA data on the Spitzer First Look Survey. By demanding objects to be...

Star Forming Galaxies at z~6 and Reionization (2005)

Bunker, Andrew, Stanway, Elizabeth, Ellis, Richard, McMahon, Richard, Eyles, Laurence, Lacy, Mark

We determine the abundance of i'-band drop-outs in the HST/ACS GOODS surveys and the Hubble Ultra Deep Field (UDF). The majority of these sources are likely to be z~6 galaxies whose flux decrement...

The 2-850 micron SED of starforming galaxies (2005)

Sajina, Anna, Scott, Douglas, Dennefeld, Michel, Dole, Herve, Lacy, Mark, Lagache, Guilaine

We present preliminary results on a study of the 2--850 micron SEDs of a sample of 30 FIRBACK galaxies selected at 170 micron. These sources are representative of the brightest ~10% of the Cosmic...

The obscuration by dust of most of the growth of supermassive black holes (2005)

Martinez-Sansigre, Alejo, Rawlings, Steve, Lacy, Mark, Fadda, Dario, Marleau, Francine R., Simpson, Chris, ...

Supermassive black holes underwent periods of exponential growth during which we seem them as quasars in the distant Universe. The summed emission from these quasars generates the cosmic X-ray...

Detecting Clusters of Galaxies at High Redshift with the Spitzer Space Telescope (2005)

Wilson, Gillian, Muzzin, Adam, Lacy, Mark, Team, The FLS

We present an infrared adaptation of the Cluster Red-Sequence method. We modify the two filter technique of Gladders & Yee (2000) to identify clusters based on their R-[3.6] color. We apply the...

Evolution of the 3.6 micron Cluster Luminosity Function (2005)

Muzzin, Adam, Wilson, Gillian, Lacy, Mark

We have measured the 3.6 micron cluster luminosity function (LF) using a sample of 123 galaxy clusters selected from the 4 degree^2 Spitzer First Look Survey (FLS). The clusters were selected on the...

Chandra Observations of 12 Luminous Red Quasars (2005)

Urrutia, Tanya, Lacy, Mark, Gregg, Michael D., Becker, Robert H.

We present results of a study of 12 dust-reddened quasars with 0.4 < z < 2.65 and reddenings in the range 0.15 < E(B-V) < 1.7. We obtained ACIS-S X-ray spectra of these quasars, estimated the column...

Spitzer Imaging of i'-drop Galaxies: Old Stars at z~6 (2005)

Eyles, Laurence, Bunker, Andrew, Stanway, Elizabeth, Lacy, Mark, Ellis, Richard, Doherty, Michelle

We present new evidence for mature stellar populations with ages >100Myr in massive galaxies (M_stellar>10^10M_sun) seen at a time when the Universe was less than 1Gyr old. We analyse the prominent...

The 2-850 micron SED of starforming galaxies (2004)

Sajina, Anna, Scott, Douglas, Dennefeld, Michel, Dole, Herve, Lacy, Mark, Lagache, Guilaine

We present preliminary results on a study of the 2--850 micron SEDs of a sample of 30 FIRBACK galaxies selected at 170 micron. These sources are representative of the brightest ~10% of the Cosmic...

Penetrating Dust Tori in AGN (2004)

Canalizo, Gabriela, Max, Claire, Antonucci, Robert, Whysong, David, Stockton, Alan, Lacy, Mark

We present preliminary results from high resolution (~ 0.05") adaptive optics observations of Cygnus A. The images show a bi-conic structure strongly suggestive of an obscuring torus around a quasar...

The First Measurements of Galaxy Clustering from IRAC Data of the Spitzer First Look Survey (2004)

Fang, Fan, Shupe, David L., Wilson, Gillian, Lacy, Mark, Fadda, Dario, Jarrett, Tom, ...

We present the first results of the angular auto-correlation function of the galaxies detected by the Infrared Array Camera (IRAC) instrument in the First Look Survey (FLS) of the Spitzer Space...

Colors and magnitudes of quasar host galaxies at high redshift (2004)

Ridgway, Susan E., Heckman, Tim, Lacy, Mark

We discuss the results so far of a program to image in the rest-frame optical and near-UV the host galaxies of a sample of 5 high redshift (z ~ 2–3) radio-quiet quasars with nuclear luminosities...

FIRST-2MASS Sources Below the APM Detection Threshold: A Population of Highly Reddened Quasars (2004)

Glikman, Eilat, Gregg, Michael D., Lacy, Mark, Helfand, David J., Becker, Robert H., White, Richard L.

We have constructed a sample of bright near-infrared sources which are detected at radio wavelengths but undetected on the POSS I plates in order to search for a population of dust-obscured quasars....

The 2-850 micron SED of starforming galaxies (2004)

Sajina, Anna, Scott, Douglas, Dennefeld, Michel, Dole, Herve, Lacy, Mark, Lagache, Guilaine

We present preliminary results on a study of the 2--850 micron SEDs of a sample of 30 FIRBACK galaxies selected at 170 micron. These sources are representative of the brightest ~10% of the Cosmic...

The 2-850 micron SED of starforming galaxies (2004)

Sajina, Anna, Scott, Douglas, Dennefeld, Michel, Dole, Herve, Lacy, Mark, Lagache, Guilaine

We present preliminary results on a study of the 2--850 micron SEDs of a sample of 30 FIRBACK galaxies selected at 170 micron. These sources are representative of the brightest ~10% of the Cosmic...

The Aligned z ~ 1 Radio Galaxy 3C 280 (2003)

Ridgway, Susan E., Stockton, Alan, Lacy, Mark

The z~1 radio galaxy 3C280 has a striking rest-frame UV morphology, with multiple line and continuum components precisely aligned with the radio structure, including an obvious semi-circular arc. We...

Imaging and spectroscopy of galaxies associated with two z~0.7 damped Lyman-alpha absorption systems (2003)

Lacy, Mark, Becker, Robert H., Storrie-Lombardi, Lisa J., Gregg, Michael D., Urrutia, Tanya, White, Richard L., ...

We have identified galaxies near two quasars which are at the redshift of damped Lyman-alpha (DLA) systems in the UV spectra of the quasars. Both galaxies are actively forming stars. One galaxy has a...

Two 100 Mpc-scale structures in the 3-D distribution of radio galaxies and their implications (2003)

Brand, Kate, Rawlings, Steve, Hill, Gary J., Lacy, Mark, Mitchell, Ewan, Tufts, Joe

We present unequivocal evidence for a huge (~80 x 100 x 100 Mpc^3) super-structure at redshift z=0.27 in the 3-D distribution of radio galaxies from the TONS08 sample, confirming tentative evidence...

Giant Lya nebulae associated with high redshift radio galaxies (2003)

Reuland, Michiel, Van Breugel, Wil, Roettgering, Huub, De Vries, Wim, Stanford, S. A., Dey, Arjun, ...

We report deep Keck narrow-band Lya images of the luminous z > 3 radio galaxies 4C 41.17, 4C 60.07, and B2 0902+34. The images show giant, 100-200 kpc scale emission line nebulae, centered on these...

Massive Black Holes at High Redshifts (2003)

Lacy, Mark

Black holes with masses M_BH~10^{8.5} M_Sun dominate the accretion history of the Universe. These black hole masses are typical of those found in radio-selected galaxies today, suggesting that the...

Using radio galaxies to find super-structures (2003)

Brand, Kate, Rawlings, Steve, Hill, Gary J., Lacy, Mark

Radio galaxies are excellent at tracing large-scale structure due to their high bias. We present new results from the TONS08 radio galaxy redshift survey. We find unequivocal evidence for a huge (at...

The production mechanism of radio jets in AGN and quasar grand unification (2002)

Lacy, Mark

Recent advances in estimating black hole masses for AGN show that radio luminosity is dependent on black hole mass and accretion rate. In this paper we outline a possible scheme for unifying...

Observations of quasar hosts with adaptive optics at Lick Observatory (2002)

Lacy, Mark, Gates, Elinor L., Ridgway, Susan E., De Vries, Wim, Canalizo, Gabriela, Lloyd, James P., ...

We present near-infrared H-band observations of the hosts of three z~1 quasars from the Sloan Digital Sky Survey made with the adaptive optics system at Lick Observatory. We derive a PSF for each...

Optical spectroscopy of radio galaxies in the 7C Redshift Survey (2002)

Willott, Chris J., Rawlings, Steve, Blundell, Katherine M., Lacy, Mark, Hill, Gary J., Scott, Susan E.

We present optical spectroscopy of all 49 radio galaxies in the 7C-I and 7C-II regions of the 7C Redshift Survey (7CRS). The low-frequency (151 MHz) selected 7CRS sample contains all sources with...

The Reddest Quasars (2001)

Gregg, Michael D., Lacy, Mark, White, Richard L., Glikman, Eilat, Helfand, David, Becker, Robert H., ...

In a survey of quasar candidates selected by matching the FIRST and 2MASS catalogs, we have found two extraordinarily red quasars. FIRST J013435.7-093102 is a 1 Jy source at z=2.216 and has B-K > 10,...

On the redshift cut-off for steep-spectrum radio sources (2001)

Jarvis, Matt J., Rawlings, Steve, Willott, Chris J., Blundell, Katherine M., Eales, Steve, Lacy, Mark

We use three samples (3CRR, 6CE and 6C*) selected at low radio frequency to constrain the cosmic evolution in the radio luminosity function (RLF) for the `most luminous' steep-spectrum radio sources....

A sample of 6C radio sources designed to find objects at redshift > 4: II --- spectrophotometry and emission line properties (2001)

Jarvis, Matt J., Rawlings, Steve, Lacy, Mark, Blundell, Katherine M., Bunker, Andrew J., Eales, Steve, ...

(Abridged) This is the second in a series of three papers which present and interpret basic observational data on the 6C* 151-MHz radio sample: a low-frequency selected sample which exploits...

The FIRST Bright Quasar Survey III. The South Galactic Cap (2001)

Becker, Robert H., White, Richard L., Gregg, Michael D., Laurent-Muehleisen, Sally A., Brotherton, Michael S., Impey, Chris D., ...

We present the results of an extension of the FIRST Bright Quasar Survey (FBQS) to the South Galactic cap, and to a fainter optical magnitude limit. Radio source counterparts with SERC R magnitudes...

Two-colour photometric selection of high redshift galaxies (2001)

Stevens, Robin, Lacy, Mark

In this paper we describe a set of models to predict the colours of galaxies over a wide range of redshifts. We present example output from the simulations, and discuss their application to the...

A sample of 6C radio sources with virtually complete redshifts. II - optical spectroscopy (2000)

Rawlings, Steve, Eales, Steve, Lacy, Mark

This is the second of two papers presenting basic observational data on the 6CE sample of extragalactic radio sources. It presents the results of optical spectroscopy which has yielded virtually...

The radio luminosity function from the low-frequency 3CRR, 6CE & 7CRS complete samples (2000)

Willott, Chris J., Rawlings, Steve, Blundell, Katherine M., Lacy, Mark, Eales, Stephen A.

We measure the radio luminosity function (RLF) of steep-spectrum radio sources using three redshift surveys of flux-limited samples selected at low (151 & 178 MHz) radio frequency, low-frequency...

Discovery of a Classic FR-II Broad Absorption Line Quasar from the FIRST Survey (2000)

Gregg, Michael D., Becker, Robert H., Brotherton, Michael S., Laurent-Muehleisen, Sally A., Lacy, Mark, White, Richard L.

We have discovered a remarkable quasar, FIRST J101614.3+520916, whose optical spectrum shows unambiguous broad absorption features while its double-lobed radio morphology and luminosity clearly...

Radio Galaxy Clustering at z~0.3 (2000)

Lacy, Mark

Radio galaxies are uniquely useful as probes of large-scale structure as their uniform identification with giant elliptical galaxies out to high redshift means that the evolution of their bias factor...

The quasar fraction in low-frequency selected complete samples and implications for unified schemes (2000)

Willott, Chris J., Rawlings, Steve, Blundell, Katherine M., Lacy, Mark

Low-frequency radio surveys are ideal for selecting orientation-independent samples of extragalactic sources because the sample members are selected by virtue of their isotropic steep-spectrum...

The Evolution of the Stellar Hosts of Radio Galaxies (2000)

Lacy, Mark, Bunker, Andrew J., Ridgway, Susan E.

We present new near-infrared images of z>0.8 radio galaxies from the flux-limited 7C-III sample of radio sources for which we have recently obtained almost complete spectroscopic redshifts. The 7C...

HST imaging of two z>4 radio galaxies (1999)

Lacy, Mark

We have imaged 8C 1435+635 (z=4.25; Lacy et al. 1994; Spinrad, Dey & Graham 1995) and 6C 0140+326 (z=4.41; Rawlings et al. 1996) in both continuum and Lyalpha plus continuum bands with the HST. Our...

The importance of radio sources in accounting for the highest mass black holes (1999)

Lacy, Mark, Ridgway, Susan, Trentham, Neil

The most massive black holes lie in the most massive elliptical galaxies, and at low-z all radio-loud AGNs lie in giant ellipticals. This strongly suggests a link between radio-loudness and black...

No evidence for a `redshift cut-off' for the most powerful classical double radio sources (1999)

Jarvis, Matt J., Rawlings, Steve, Willott, Chris J., Blundell, Katherine M., Eales, Steve, Lacy, Mark

We use three samples (3CRR, 6CE and 6C*) to investigate the radio luminosity function (RLF) for the `most powerful' low-frequency selected radio sources. We find that the data are well fitted by a...

The emission line - radio correlation for radio sources using the 7C Redshift Survey (1999)

Willott, Chris J., Rawlings, Steve, Blundell, Katherine M., Lacy, Mark

We have used narrow emission line data from the new 7C Redshift Survey to investigate correlations between the narrow-line luminosities and the radio properties of radio galaxies and steep-spectrum...

A complete sample of radio sources in the North Ecliptic Cap, selected at 38 MHz -- III. further imaging observations and the photometric properties of the sample (1999)

Lacy, Mark, Kaiser, Mary Elizabeth, Hill, Gary J., Rawlings, Steve, Leyshon, Gareth

Further imaging observations of a sample of radio sources in the North Ecliptic Cap are presented and a number of new identifications are made. Using redshifts from spectroscopic data presented in a...

Optical spectroscopy of two overlapping, flux-density-limited samples of radio sources in the North Ecliptic Cap, selected at 38 MHz and 151 MHz (1999)

Lacy, Mark, Rawlings, Steve, Hill, Gary J., Bunker, Andrew J., Ridgway, Susan E., Stern, Daniel

We present the results of optical spectroscopy of two flux-density-limited samples of radio sources selected at frequencies of 38 and 151 MHz in the same region around the North Ecliptic Cap, the...

Radio-optical alignments in a low radio luminosity sample (1999)

Lacy, Mark, Ridgway, Susan E., Wold, Margrethe, Lilje, Per B., Rawlings, Steve

We present an optically-based study of the alignment between the radio axes and the optical major axes of eight z~0.7 radio galaxies in a 7C sample. The radio galaxies in this sample are ~20-times...

Thermal-infrared imaging of 3C radio galaxies at z~1 (1999)

Simpson, Chris, Rawlings, Steve, Lacy, Mark

We present the results of a programme of thermal-IR imaging of nineteen z~1 radio galaxies from the 3CR and 3CRR samples. We detect emission at L' (3.8um) from four objects; in each case the emission...

Quasars from the 7C Survey - I:sample selection and radio maps (1999)

Riley, Julia, Rawlings, Steve, McMahon, Richard, Blundell, Katherine, Miller, Philip, Lacy, Mark, ...

We describe the selection of candidate radio-loud quasars obtained by cross-matching radio source positions from the low-frequency (151 MHz) 7C survey with optical positions from five pairs of EO...

IRAS F10214+4724: the inner 100pc (1998)

Lacy, Mark, Rawlings, Steve, Serjeant, Stephen

We use new near-infrared spectroscopy and our published optical spectroscopy of the gravitationally-lensed Seyfert-2 galaxy F10214+4724 to study both the links between the starburst and AGN in this...

A radio-jet -- galaxy interaction in 3C441 (1998)

Lacy, Mark, Rawlings, Steve, Blundell, Katherine M., Ridgway, Susan E.

Multi-wavelength imaging and spectroscopy of the z=0.708 radio galaxy 3C441 and a red aligned optical/infrared component are used to show that the most striking aspect of the radio-optical...

A spectroscopic study of IRAS F10214+4724 (1998)

Serjeant, Stephen, Rawlings, Steve, Lacy, Mark, McMahon, Richard G., Lawrence, Andy, Rowan-Robinson, Michael, ...

The z=2.286 IRAS galaxy F10214+4724 remains one of the most luminous galaxies in the Universe, despite its gravitational lens magnification. We present optical and near-infrared spectra of...

Searches for galaxies at z > 4 through Lyman-limit imaging (1997)

Stevens, Robin, Lacy, Mark, Rawlings, Steve

We present preliminary results of a search for galaxies at z>4 through Lyman-limit imaging of the fields of known high-redshift radio-galaxies. Objects were selected by means of their broad-band...

The Radio-Optical Correlation in Steep-Spectrum Quasars (1997)

Serjeant, Stephen, Rawlings, Steve, Maddox, Stephen J., Baker, Joanne C., Clements, Dave, Lacy, Mark, ...

Using complete samples of steep-spectrum quasars, we present evidence for a correlation between radio and optical luminosity which is not caused by selection effects, nor caused by an orientation...

A complete sample of quasars from the 7C redshift survey (1997)

Willott, Chris J., Rawlings, Steve, Blundell, Katherine M., Lacy, Mark

We present details of a new sample of radio-loud quasars drawn from 0.013 sr of the 7C Redshift Survey. This sample is small (21 quasars) but complete in that every object with an unresolved nucleus...

Cosmology with redshift surveys of radio sources (1997)

Rawlings, Steve, Blundell, Katherine M., Lacy, Mark, Willott, Chris J., Eales, Stephen A.

We use the K-z relation for radio galaxies to illustrate why it has proved difficult to obtain definitive cosmological results from studies based entirely on catalogues of the brightest radio...

HST imaging of redshift z>0.5 7C and 3C Quasars (1997)

Serjeant, Stephen, Rawlings, Steve, Lacy, Mark

We present preliminary results from HST imaging of radio-loud quasar hosts, covering a ~x100 range in radio luminosity but in a narrow redshift range (0.5 to 0.65). The sample was selected from our...

A first sample of faint radio sources with virtually complete redshifts: I. Infrared images, the Hubble diagram, and the alignment effect (1997)

Eales, Stephen, Rawlings, Steve, Law-Green, Duncan, Cotter, Garret, Lacy, Mark

We have obtained redshifts and infrared images for a sample of faint B2/6C radio sources whose fluxes are about six times fainter than those of sources in the bright 3C sample. We now have...

Optical and infrared investigation towards the z=3.8 quasar pair PC1643+4631A&B (1996)

Saunders, Richard, Baker, Joanne C., Bremer, Malcolm N., Bunker, Andrew J., Cotter, Garret, Eales, Steve, ...

In a companion paper (Paper I: Jones et al. 1996) we report the discovery of a cosmic microwave background decrement, indicative of a distant cluster with mass ~10^{15} solar masses, towards the...

Evidence for a black hole in a radio-quiet quasar nucleus (1996)

Blundell, Katherine M., Beasley, Anthony J., Lacy, Mark, Garrington, Simon

We present the first milli-arcsecond resolution radio images of a radio-quiet quasar, detecting a high brightness temperature core with data from the VLBA. On maps made with lower-frequency data from...

Evidence for a Black Hole in a Radio-Quiet Quasar Nucleus (1996)

Katherine M. Blundell, Anthony J. Beasley, Mark Lacy, Simon T. Garrington

We present the first milli-arcsecond resolution radio images of a radio-quiet quasar, detecting a high brightness temperature core with data from the VLBA. On maps made with lower-frequency data from...

Spectroscopic Evidence That the Extreme Properties of IRAS F10214+4724 are due to Gravitational Lensing (1995)

Serjeant, Stephen, Lacy, Mark, Rawlings, Steve, King, Lindsay, Clements, D. L.

The extreme bolometric luminosity of IRAS F10214+4724, and in particular the huge mass in molecular gas inferred from the CO line fluxes have led to suggestions that this is a giant galaxy in the...