Johan Richard

LoCuSS: First Results from Strong-lensing Analysis of 20 Massive Galaxy Clusters at z~0.2 (2009)

Richard, Johan, Smith, Graham, Kneib, Jean-Paul, Ellis, Richard, Sanderson, Alastair, Pei, Liuyi, ...

We present a statistical analysis of a sample of 20 strong lensing clusters drawn from the Local Cluster Substructure Survey (LoCuSS), based on high resolution Hubble Space Telescope imaging of the...

Hubble Space Telescope Observations of a Spectacular New Strong-lensing Galaxy Cluster - MACSJ1149.5+2223 at z=0.544 (2009)

Smith, Graham P., Ebeling, Harald, Limousin, Marceau, Kneib, Jean-Paul, Swinbank, A. M., Ma, Cheng-Jiun, ...

We present Advanced Camera for Surveys observations of MACSJ1149.5+2223, an X-ray luminous galaxy cluster at z=0.544 discovered by the Massive Cluster Survey. The data reveal at least seven...

Abell 370 revisited: refurbished Hubble imaging of the first strong lensing cluster (2009)

Richard, Johan, Kneib, Jean-Pau, Limousin, Marceau, Edge, Alastair, Jullo, Eric

We present a strong lensing analysis of the galaxy cluster Abell 370 (z=0.375) based on the recent multicolor ACS images obtained as part of the Early Release Observation (ERO) that followed the...

Resolved Spectroscopy of Gravitationally-Lensed Galaxies: Recovering Coherent Velocity Fields in Sub-Luminous z~2-3 Galaxies (2009)

Jones, Tucker, Swinbank, Mark, Ellis, Richard, Richard, Johan, Stark, Dan

We present spatially-resolved dynamics for six strongly lensed star-forming galaxies at z=1.7-3.1, each enlarged by a linear magnification factor ~8. Using the Keck laser guide star AO system and the...

A Spatially Resolved Map of the Kinematics, Star-Formation and Stellar Mass Assembly in a Star-Forming Galaxy at z=4.9 (2009)

Swinbank, Mark, Webb, Tracy, Richard, Johan, Bower, Richard, Ellis, Richard, Illingworth, Garth, ...

We present a detailed study of the spatially resolved kinematics, star-formation and stellar mass in a highly amplified galaxy at z=4.92 behind the lensing cluster MS1358+62. We use the observed...

LoCuSS: A Comparison of Sunyaev-Zel'dovich Effect and Gravitational-Lensing Measurements of Galaxy Clusters (2009)

Marrone, Daniel P., Smith, Graham P., Richard, Johan, Joy, Marshall, Bonamente, Massimiliano, Hasler, Nicole, ...

We present the first measurement of the relationship between the Sunyaev-Zel'dovich effect (SZE) signal and the mass of galaxy clusters that uses gravitational lensing to measure cluster mass, based...

LoCuSS: A Comparison of Sunyaev-Zel'dovich Effect and Gravitational Lensing Measurements of Galaxy Clusters (2009)

Marrone, Daniel P., Smith, Graham P., Richard, Johan, Joy, Marshall, Bonamente, Massimiliano, Hasler, Nicole, ...

We present the first measurement of the relationship between the Sunyaev-Zel'dovich effect signal and the mass of galaxy clusters that uses gravitational lensing to measure cluster mass, based on 14...

Strong Lensing as a Probe of the Mass Distribution Beyond the Einstein Radius. Mass & Light in SL2S J0544-0121, a Galaxy Group at z=0.35 (2009)

Limousin, Marceau, Jullo, Eric, Richard, Johan, Cabanac, Remi, Kneib, Jean-Paul, Gavazzi, Raphael, ...

A precise modelling of a strong lensing system can be affected by some external mass distribution. In this article, we propose to turn this bother to our advantage and to use precise strong lensing...

Detection of PAH and Far-Infrared Emission from the Cosmic Eye: Probing the Dust and Star Formation of Lyman Break Galaxies (2009)

Siana, Brian, Smail, Ian, Swinbank, A. Mark, Richard, Johan, Teplitz, Harry I., Coppin, Kristen E. K., ...

We report the results of a Spitzer infrared study of the Cosmic Eye, a strongly lensed, L*_UV Lyman Break Galaxy (LBG) at z=3.074. We obtained Spitzer IRS spectroscopy as well as MIPS 24 and 70...

Keck spectroscopic survey of strongly lensed galaxies in Abell 1703: further evidence for a relaxed, unimodal cluster (2009)

Richard, Johan, Pei, Liuyi, Limousin, Marceau, Jullo, Eric, Kneib, Jean-Paul

Strong gravitational lensing is a unique tool to model with great accuracy the inner mass distribution of massive galaxy clusters. In particular, clusters with large Einstein radii provide a wealth...

The formation and assembly of a typical star-forming galaxy at redshift z ≈ 3 (2008)

Stark, Daniel P., Swinbank, A. Mark, Ellis, Richard S., Dye, Simon, Smail, Ian R., Richard, Johan

Recent studies of galaxies ~2–3 Gyr after the Big Bang have revealed large, rotating disks, similar to those of galaxies today^(1,2). The existence of well-ordered rotation in galaxies during this...

The formation and assembly of a typical star-forming galaxy at z~3 (2008)

Stark, Daniel P., Swinbank, Mark, Ellis, Richard S., Dye, Simon, Smail, Ian R., Richard, Johan

Recent studies of galaxies ~2-3 Gyr after the Big Bang have revealed large, turbulent rotating systems. The existence of well-ordered rotation in galaxies during this peak epoch of cosmic star...

A Hubble and Spitzer space telescope survey for gravitationally lensed galaxies: further evidence for a significant population of low-luminosity galaxies beyond z=7 (2008)

Richard, Johan, Stark, Daniel P., Ellis, Richard S., George, Matthew R., Egami, Eiichi, Kneib, Jean-Paul, ...

We present the results of a systematic search for gravitationally lensed continuum Lyman break "dropouts" beyond a redshift 7 conducted via very deep imaging through six foreground clusters...

A Hubble & Spitzer Space Telescope Survey for Gravitationally-Lensed Galaxies: Further Evidence for a Significant Population of Low Luminosity Galaxies beyond Redshift Seven (2008)

Richard, Johan, Stark, Daniel P., Ellis, Richard S., George, Matthew R., Egami, Eiichi, Kneib, Jean-Paul, ...

We present the results of a systematic search for gravitationally-lensed continuum Lyman break `drop-outs' beyond a redshift 7 conducted via very deep imaging through six foreground clusters...

A Keck Survey for Gravitationally-Lensed Lyman-alpha Emitters in the Redshift Range 8.5 (2007)

Stark, Daniel P., Ellis, Richard S., Richard, Johan, Kneib, Jean-Paul, Smith, Graham P., Santos, Michael R.

We discuss new observational constraints on the abundance of faint high redshift Lyman-alpha emitters secured from a deep Keck near-infrared spectroscopic survey which utilizes the strong...

A statistical study of multiply-imaged systems in the lensing cluster Abell 68 (2007)

Richard, Johan, Kneib, Jean-Paul, Jullo, Eric, Covone, Giovanni, Limousin, Marceau, Ellis, Richard, ...

We have carried out an extensive spectroscopic survey with the Keck and VLT telescopes, targeting lensed galaxies in the background of the massive cluster Abell 68. Spectroscopic measurements are...

A Keck Survey for Gravitationally-Lensed Lyman-alpha Emitters in the Redshift Range 8.5 < z < 10.4: New Constraints on the Contribution of Low Luminosity Sources to Cosmic Reionization (2007)

Stark, Daniel P., Ellis, Richard S., Richard, Johan, Kneib, Jean-Paul, Smith, Graham P., Santos, Michael R.

We discuss new observational constraints on the abundance of faint high redshift Lyman-alpha emitters secured from a deep Keck near-infrared spectroscopic survey which utilizes the strong...

First results from the VIMOS-IFU survey of gravitationally lensing clusters at z~0.2 (2006)

Covone, Giovanni, Kneib, Jean-Paul, Soucail, Genevieve, Jullo, Eric, Richard, Johan

We present the on-going observational program of a VIMOS Integral Field Unit survey of the central regions of massive, gravitational lensing galaxy clusters at redshift z~0.2. We have observed six...

Constraining the population of 6 < z < 10 star-forming galaxies with deep near-IR images of lensing clusters (2006)

Richard, Johan, Pello, Roser, Schaerer, Daniel, Borgne, Jean-Francois Le, Kneib, Jean-Paul

(abridged) We present the first results of our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z~6-10. Deep near-IR photometry of two lensing clusters...

Constraining the population of 6 < z < 10 star-forming galaxies with deep near-IR images of lensing clusters (2006)

Richard, Johan, Pello, Roser, Schaerer, Daniel, Borgne, Jean-Francois Le, Kneib, Jean-Paul

(abridged) We present the first results of our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z~6-10. Deep near-IR photometry of two lensing clusters...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2006)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

First results from the VIMOS-IFU survey of gravitationally lensing clusters at z~0.2 (2006)

Covone, Giovanni, Kneib, Jean-Paul, Soucail, Genevieve, Jullo, Eric, Richard, Johan

We present the on-going observational program of a VIMOS Integral Field Unit survey of the central regions of massive, gravitational lensing galaxy clusters at redshift z~0.2. We have observed six...

First results from the VIMOS-IFU survey of gravitationally lensing clusters at z~0.2 (2006)

Covone, Giovanni, Kneib, Jean-Paul, Soucail, Genevieve, Jullo, Eric, Richard, Johan

We present the on-going observational program of a VIMOS Integral Field Unit survey of the central regions of massive, gravitational lensing galaxy clusters at redshift z~0.2. We have observed six...

Constraining the population of 6 < z < 10 star-forming galaxies with deep near-IR images of lensing clusters (2006)

Richard, Johan, Pello, Roser, Schaerer, Daniel, Borgne, Jean-Francois Le, Kneib, Jean-Paul

(abridged) We present the first results of our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z~6-10. Deep near-IR photometry of two lensing clusters...

First results from the VIMOS-IFU survey of gravitationally lensing clusters at z~0.2 (2006)

Covone, Giovanni, Kneib, Jean-Paul, Soucail, Genevieve, Jullo, Eric, Richard, Johan

We present the on-going observational program of a VIMOS Integral Field Unit survey of the central regions of massive, gravitational lensing galaxy clusters at redshift z~0.2. We have observed six...

Constraining the population of 6 < z < 10 star-forming galaxies with deep near-IR images of lensing clusters (2006)

Richard, Johan, Pello, Roser, Schaerer, Daniel, Borgne, Jean-Francois Le, Kneib, Jean-Paul

(abridged) We present the first results of our deep survey of lensing clusters aimed at constraining the abundance of star-forming galaxies at z~6-10. Deep near-IR photometry of two lensing clusters...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2005)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2005)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2005)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2005)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

PROPRIETES DES PREMIERES ETOILES ET GALAXIES. CONTRAINTES SUR LES MODELES DE FORMATION DES GALAXIES (2005)

Richard, Johan

Une des frontières actuelles de la cosmologie observationnelle est celle de la réionisation, époque au cours de laquelle la formation des premières étoiles et galaxies a marqué la fin des «...

Propriétés physiques des premières étoiles et galaxies. Contraintes sur les modèles de formation des galaxies (2005)

Richard, Johan

Ce travail de thèse repose sur l'analyse de trios projets observationnels destines à la détection et l'étude de sources astrophysiques extrêmement distantes. Les champs considérés ont été...

A Probable z~7 Galaxy Strongly Lensed by the Rich Cluster Abell 2218: Exploring the Dark Ages (2004)

Kneib, Jean-Paul, Ellis, Richard S., Santos, Michael R., Richard, Johan

We discuss the observational properties of a remarkably faint triply-imaged galaxy revealed in a deep z-band ACS observation of the lensing cluster A2218. A well-constrained mass model for the...

The Abundance of Low-luminosity Lyman alpha Emitters at High Redshift (2003)

Santos, Michael R., Ellis, Richard S., Kneib, Jean-Paul, Richard, Johan, Kuijken, Konrad

We derive the luminosity function of high-redshift Lyman alpha emitting sources from a deep, blind, spectroscopic survey that utilized strong-lensing magnification by intermediate-redshift clusters...