Schrabback, Tim, Hartlap, Jan, Joachimi, Benjamin, Kilbinger, Martin, Simon, Patrick, Benabed, Karim, ...
We present a tomographic cosmological weak lensing analysis of the HST COSMOS Survey. Applying our lensing-optimized data reduction, principal component interpolation for the ACS PSF, and improved...
Structure Formation by Fifth Force: Power Spectrum from N-Body Simulations (2009)
Zhao, HongSheng, Maccio', Andrea, Li, Baojiu, Hoekstra, Henk, Feix, Martin
We lay out the framework to numerically study nonlinear structure formation in the context of scalar-field-coupled cold dark matter models (phiCDM models) where the scalar field phi serves as...
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...
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...
Tian, Lanlan, Hoekstra, Henk, Zhao, Hongsheng
We study the amplitude of the weak gravitational lensing signal as a function of stellar mass around a sample of relatively isolated galaxies. This selection of lenses simplifies the interpretation...
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...
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...
The X-ray Cluster Normalization of the Matter Power Spectrum (2008)
Henry, J. Patrick, Evrard, August E., Hoekstra, Henk, Babul, Arif, Mahdavi, Andishieh
The number density of galaxy clusters provides tight statistical constraints on the matter fluctuation power spectrum normalization, traditionally phrased in terms of sigma_8, the root mean square...
Sersiclets - A Matched Filter Generalisation of Shapelets for Weak Lensing Studies (2008)
Ngan, Wai-Hin Wayne, Van Waerbeke, Ludovic, Mahdavi, Andisheh, Heymans, Catherine, Hoekstra, Henk
The precision study of dark matter using weak lensing by large scale structure is strongly constrained by the accuracy with which one can measure galaxy shapes. Several methods have been devised but...
Weak Gravitational Lensing and its Cosmological Applications (2008)
Hoekstra, Henk, Jain, Bhuvnesh
Weak gravitational lensing is a unique probe of the dark side of the universe: it provides a direct way to map the distribution of dark matter around galaxies, clusters of galaxies and on...
Handbook for the GREAT08 Challenge: An image analysis competition for cosmological lensing (2008)
Bridle, Sarah, Shawe-Taylor, John, Amara, Adam, Applegate, Douglas, Balan, Sreekumar T., Berge, Joel, ...
The GRavitational lEnsing Accuracy Testing 2008 (GREAT08) Challenge focuses on a problem that is of crucial importance for future observations in cosmology. The shapes of distant galaxies can be used...
A Multiwavelength Analysis of the Strong Lensing Cluster RCS 022434-0002.5 at z=0.778 (2007)
Hicks, Amalia K., Ellingson, Erica, Hoekstra, Henk, Gladders, Mike, Yee, Howard, Bautz, Mark, ...
We present the results of two (101 ks total) Chandra observations of the z=0.778 optically selected lensing cluster RCS022434-0002.5, along with weak lensing and dynamical analyses of this object. An...
The Masses and Shapes of Dark Matter Halos from Galaxy-Galaxy Lensing in the CFHTLS (2007)
Parker, Laura C., Hoekstra, Henk, Hudson, Michael J., Van Waerbeke, Ludovic, Mellier, Yannick
We present the first galaxy-galaxy weak lensing results using early data from the Canada-France-Hawaii Telescope Legacy Survey (CFHTLS). These results are based on ~22 sq. deg. of i' data. From this...
Comparison of weak lensing masses and X-ray properties of galaxy clusters (2007)
We present measurements of the masses of 20 X-ray luminous clusters of galaxies at intermediate redshifts, determined from a weak lensing analysis of deep archival R-band data obtained using the...
Cosmological Constraints From the 100 Square Degree Weak Lensing Survey (2007)
Benjamin, Jonathan, Heymans, Catherine, Semboloni, Elisabetta, Van Waerbeke, Ludovic, Hoekstra, Henk, Erben, Thomas, ...
We present a cosmic shear analysis of the 100 square degree weak lensing survey, combining data from the CFHTLS-Wide, RCS, VIRMOS-DESCART and GaBoDS surveys. Spanning ~100 square degrees, with a...
Multiwavelength Mass Comparisons of the z~0.3 CNOC Cluster Sample (2006)
Hicks, Amalia K., Ellingson, Erica, Hoekstra, Henk, Yee, Howard
Results are presented from a detailed analysis of optical and X-ray observations of moderate-redshift galaxy clusters from the Canadian Network for Observational Cosmology (CNOC) subsample of the...
The Shear TEsting Programme 2: Factors affecting high precision weak lensing analyses (2006)
Massey, Richard, Heymans, Catherine, Berge, Joel, Bernstein, Gary, Bridle, Sarah, Clowe, Douglas, ...
The Shear TEsting Programme (STEP) is a collaborative project to improve the accuracy and reliability of weak lensing measurement, in preparation for the next generation of wide-field surveys. We...
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...
Redshift and Shear Calibration: Impact on Cosmic Shear Studies and Survey Design (2006)
Van Waerbeke, Ludovic, White, Martin, Hoekstra, Henk, Heymans, Catherine
The cosmological interpretation of weak lensing by large-scale structures requires knowledge of the redshift distribution of the source galaxies. Current lensing surveys are often calibrated using...
Cosmological Constraints from the Red-Sequence Cluster Survey (2006)
Gladders, Michael D., Yee, H. K. C., Majumdar, Subhabrata, Barrientos, L. Felipe, Hoekstra, Henk, Hall, Patrick B., ...
[abridged] We present a first cosmological analysis of a refined cluster catalog from the Red-Sequence Cluster Survey (RCS). The input cluster sample is derived from 72.07 square degrees of imaging...
Schimd, Carlo, Tereno, Ismael, Uzan, Jean-Philippe, Mellier, Yannick, Van Waerbeke, Ludovic, Semboloni, Elisabetta, ...
Dark energy can be investigated in two complementary ways, by considering either general parameterizations or physically well-defined models. Following the second route, we explore the constraints on...
The Shear Testing Programme - I. Weak lensing analysis of simulated ground-based observations (2006)
Heymans, Catherine, Van Waerbeke, Ludovic, Bacon, David, Berge, Joel, Bernstein, Gary, Bertin, Emmanuel, ...
The Shear Testing Programme (STEP) is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for the next generation of wide-field surveys. In...
Weak lensing constraints on galaxy halos (2005)
Weak gravitational lensing has become an important tool to study the properties of dark matter halos around galaxies, thanks to the advent of large panoramic cameras on 4m class telescopes. This area...
Mass-to-Light Ratios of Galaxy Groups from Weak Lensing (2005)
Parker, Laura C., Hudson, Michael J., Carlberg, Ray G., Hoekstra, Henk
We present the findings of our weak lensing study of a sample of 116 CNOC2 galaxy groups. The lensing signal is used to estimate the mass-to-light ratio of these galaxy groups. The best fit...
The Shear TEsting Programme 1: Weak lensing analysis of simulated ground-based observations (2005)
Heymans, Catherine, Van Waerbeke, Ludovic, Bacon, David, Berge, Joel, Bernstein, Gary, Bertin, Emmanuel, ...
The Shear TEsting Programme, STEP, is a collaborative project to improve the accuracy and reliability of all weak lensing measurements in preparation for the next generation of wide-field surveys. In...
An algorithm to detect blends with eclipsing binaries in planet transit searches (2005)
Hoekstra, Henk, Wu, Yanqin, Udalski, Andrzej
We present an algorithm that can detect blends of bright stars with fainter, un-associated eclipsing binaries. Such systems contaminate searches for transiting planets, in particular in crowded...
Large scale systematic signals in weak lensing surveys (2004)
Vale, Chris, Hoekstra, Henk, Van Waerbeke, Ludovic, White, Martin
We use numerical simulations to model the effect of seeing and extinction modulations on weak lensing surveys. We find that systematic fluctuations in the shear amplitude and source depth can give...
Mapping the dark matter using weak lensing (2003)
Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. The advent of panoramic cameras on 4m class...
Properties of galaxy dark matter halos from weak lensing (2003)
Hoekstra, Henk, Yee, Howard K. C., Gladders, Michael D.
We present the results of a study of the average mass profile around galaxies using weak gravitational lensing. We use 45.5 deg^2 of R_C band imaging data from the Red-Sequence Cluster Survey (RCS)...
Properties of galaxy dark matter halos from weak lensing (2003)
Hoekstra, Henk, Yee, Howard K. C., Gladders, Michael D.
We present the results of a study of weak lensing by galaxies based on 45.5 deg$^2$ of $R_C$ band imaging data from the Red-Sequence Cluster Survey (RCS). We present the first weak lensing detection...
The effect of imperfect corrections of PSF anisotropy on cosmic shear measurements (2003)
Current measurements of the weak lensing signal induced by large scale structure provide useful constraints on a range of cosmological parameters. However, the ultimate succes of this technique...
The Incidence of Strong-Lensing Clusters in the Red-Sequence Cluster Survey (2003)
Gladders, Michael D., Hoekstra, Henk, Yee, H. K. C., Hall, Patrick B., Barrientos, L. Felipe
The incidence of giant arcs due to strong-lensing clusters of galaxies is known to be discrepant with current theoretical expectations. This result derives from a comparison of several cluster...
Contaldi, Carlo R., Hoekstra, Henk, Lewis, Antony
We use Cosmic Microwave Background (CMB) observations together with the Red-sequence Cluster Survey (RCS) weak lensing results to derive constraints on a range of cosmological parameters. This...
How well can we determine cluster mass profiles from weak lensing? (2002)
Weak gravitational lensing provides a direct way to study the mass distribution of clusters of galaxies at large radii. Unfortunately, large scale structure along the line of sight also contributes...
Weak lensing study of galaxy biasing (2002)
Hoekstra, Henk, Van Waerbeke, Ludo, Gladders, Michael D., Mellier, Yannick, Yee, H. K. C.
We combine weak lensing measurements from the Red-Sequence Cluster Survey and the VIRMOS-DESCART survey, and present the first direct measurements of the bias parameter b and the galaxy-mass...
Current status of weak gravitational lensing (2002)
Hoekstra, Henk, Yee, Howard, Gladders, Mike
Weak gravitational lensing of distant galaxies by foreground structures has proven to be a powerful tool to study the mass distribution in the universe. Nowadays, attention has shifted from clusters...
Constraints on Omega_m and sigma_8 from weak lensing in RCS fields (2002)
Hoekstra, Henk, Yee, Howard, Gladders, Mike
We have analysed 53 square degrees of imaging data from the Red-Sequence Cluster Survey (RCS), and measured the excess correlations in the shapes of galaxies on scales out to ~1.5 degrees. We...
A measurement of weak lensing by large scale structure in RCS fields (2002)
Hoekstra, Henk, Yee, Howard K. C., Gladders, Michael D., Barrientos, L. Felipe, Hall, Patrick B., Infante, Leopoldo
We have analysed ~24 square degrees of R_C-band imaging data from the Red-Sequence Cluster Survey (RCS), and measured the excess correlations between galaxy ellipticities on scales ranging from 1 to...
Lensing results from the Red-sequence Cluster Survey (2002)
Hoekstra, Henk, Yee, Howard, Gladders, Mike
We present a variety of weak lensing results based on the ongoing analysis of R_C-band imaging data from the Red-Sequence Cluster Survey (RCS). We briefly discuss the weak lensing signal induced by...
The Red-Sequence Cluster Survey: first lensing results (2001)
Hoekstra, Henk, Yee, H. K. C., Gladders, Michael D.
The Red-Sequence Cluster Survey (RCS) is a 100 deg^2 galaxy cluster survey designed to provide a large sample of optically selected clusters of galaxies with redshifts 0.1
Hoekstra, Henk, Franx, Marijn, Kuijken, Konrad, Van Dokkum, Pieter G.
We have detected the weak lensing signal induced by the cluster of galaxies MS 2053-04 (z=0.58) from a two-colour mosaic of 6 HST WFPC2 images. The best fit singular isothermal sphere model to the...
Measurement of the bias parameter from weak lensing (2001)
Hoekstra, Henk, Yee, Howard K. C., Gladders, Michael D.
We have measured the correlation between the lensing signal induced by (dark) matter and number counts of galaxies on scales ranging from 0.15-3.0 h_{50}^{-1} Mpc (which correspond to aperture radii...
First weak lensing results from the Red-Sequence Cluster Survey (2001)
Hoekstra, Henk, Yee, Howard, Gladders, Mike
The Red-Sequence Cluster Survey (RCS) is a 100 square degree galaxy cluster survey designed to provide a large sample of optically selected clusters of galaxies with redshifts 0.1
U, B and r band luminosity functions of galaxies in the Coma cluster (2001)
Beijersbergen, Marco, Hoekstra, Henk, Van Dokkum, Pieter G., Van Der Hulst, Thijs
We present a deep multi-colour CCD mosaic of the Coma cluster (Abell 1656), covering 5.2 deg^2 in the B and r bands, and 1.3 deg^2 in the U band. This large, homogeneous data set provides a valuable...
The effect of distant large scale structure on weak lensing mass estimates (2001)
We quantify the uncertainty in weak lensing mass estimates of clusters of galaxies, caused by distant (uncorrelated) large scale structure along the line of sight. We find that the effect is fairly...
Mass and mass-to-light ratio of galaxy groups from weak lensing (1999)
Hoekstra, Henk, Franx, Marijn, Kuijken, Konrad
We have measured for the first time the weak lensing signal due to groups of galaxies. The groups are at intermediate redshifts, and have been identified in the CNOC2 field survey, which was kindly...