Powell, Leila C., Kay, Scott T., Babul, Arif
In this paper, we undertake a study to determine what insight can be reliably gleaned from the comparison of the X-ray and the weak lensing mass maps of galaxy clusters. We do this by investigating...
Crain, Robert A., Theuns, Tom, Vecchia, Claudio Dalla, Eke, Vincent R., Frenk, Carlos S., Jenkins, Adrian, ...
[Abridged] We present the first results of hydrodynamical simulations that follow the formation of galaxies to z=0 in spherical regions of radius ~20 Mpc/h drawn from the Millennium Simulation. The...
Statistics of the Sunyaev-Zel'dovich Effect power spectrum (2009)
Peel, Michael W., Battye, Richard A., Kay, Scott T.
Using large numbers of simulations of the microwave sky, incorporating the Cosmic Microwave Background (CMB) and the Sunyaev-Zel'dovich (SZ) effect due to clusters, we investigate the statistics of...
Early assembly of the most massive galaxies (2009)
Collins, Chris A., Stott, John P., Hilton, Matt, Kay, Scott T., Stanford, S. Adam, Davidson, Michael, ...
The current consensus is that galaxies begin as small density fluctuations in the early Universe and grow by in situ star formation and hierarchical merging. Stars begin to form relatively quickly in...
Hilton, Matt, Stanford, S. Adam, Stott, John P., Collins, Chris A., Hoyle, Ben, Davidson, Michael, ...
We present a study of the morphological fractions and color-magnitude relation in the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.46, using a combination of...
Measurement of the dark matter velocity anisotropy in galaxy clusters (2009)
Host, Ole, Hansen, Steen H., Piffaretti, Rocco, Morandi, Andrea, Ettori, Stefano, Kay, Scott T., ...
The internal dynamics of a dark matter structure may have the remarkable property that the local temperature in the structure depends on direction. This is parametrized by the velocity anisotropy...
Crain, Robert A., Theuns, Tom, Dalla Vecchia, Claudio, Eke, Vincent R., Frenk, Carlos S., Jenkins, Adrian, ...
We present the first results of hydrodynamical simulations that follow the formation of galaxies to the present day in nearly spherical regions of radius ~ 20 h^-1 Mpc/h drawn from the Millennium...
Measurement of the dark matter velocity anisotropy in galaxy clusters (2008)
Host, Ole, Hansen, Steen H., Piffaretti, Rocco, Morandi, Andrea, Ettori, Stefano, Kay, Scott T., ...
The internal dynamics of a dark matter structure may have the remarkable property that the local temperature in the structure depends on direction. This is parametrized by the velocity anisotropy...
Dark matter halo concentrations in the Wilkinson Microwave Anisotropy Probe year 5 cosmology (2008)
Duffy, Alan R., Schaye, Joop, Kay, Scott T., Vecchia, Claudio Dalla
We use a combination of three large N-body simulations to investigate the dependence of dark matter halo concentrations on halo mass and redshift in the WMAP year 5 cosmology. The median relation...
Sahlén, Martin, Viana, Pedro T. P., Liddle, Andrew R., Romer, A. Kathy, Davidson, Michael, Sabirli, Kivanc, ...
We forecast the constraints on the values of sigma_8, Omega_m, and cluster scaling relation parameters which we expect to obtain from the XMM Cluster Survey (XCS). We assume a flat Lambda-CDM...
The XMM Cluster Survey: The Dynamical State of XMMXCS J2215.9-1738 at z=1.457 (2007)
Hilton, Matt, Collins, Chris A., Stanford, S. Adam, Lidman, Chris, Dawson, Kyle S., Davidson, Michael, ...
We present new spectroscopic observations of the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.457, obtained with the DEIMOS instrument at the W. M. Keck...
Powell, Leila C., Kay, Scott T., Babul, Arif, Mahdavi, Andisheh
Various differences in galaxy cluster properties derived from X-ray and weak lensing observations have been highlighted in the literature. One such difference is the observation of mass...
The Sunyaev-Zel'dovich temperature of the intracluster medium (2007)
Kay, Scott T., Powell, Leila C., Liddle, Andrew R., Thomas, Peter A.
The relativistic Sunyaev-Zel'dovich (SZ) effect offers a method, independent of X-ray, for measuring the temperature of the intracluster medium (ICM) in the hottest systems. Here, using...
Kay, Scott T., Da Silva, Antonio C., Aghanim, Nabila, Blanchard, Alain, Liddle, Andrew R., Puget, Jean-Loup, ...
We present results from a study of the X-ray cluster population that forms within the CLEF cosmological hydrodynamics simulation, a large N-body/SPH simulation of the Lambda CDM cosmology with...
The baseline intracluster entropy profile from gravitational structure formation (2005)
Voit, G. Mark, Kay, Scott T., Bryan, Greg L.
The radial entropy profile of the hot gas in clusters of galaxies tends to follow a power law in radius outside of the cluster core. Here we present a simple formula giving both the normalization and...
Muanwong, Orrarujee, Kay, Scott T., Thomas, Peter A.
We investigate the redshift dependence of X-ray cluster scaling relations drawn from three hydrodynamic simulations of the LCDM cosmology: a Radiative model that incorporates radiative cooling of the...
Van Kampen, Eelco, Percival, Will J., Crawford, Miller, Dunlop, James S., Scott, Susie E., Bevis, Neil, ...
We present predictions for the angular correlation function and redshift distribution for SHADES, the SCUBA HAlf-Degree Extragalactic Survey, which will yield a sample of around 300 sub-mm sources in...
Cosmological simulations of the intracluster medium (2004)
Kay, Scott T., Thomas, Peter A., Jenkins, Adrian, Pearce, Frazer R.
We investigate the properties of the intracluster medium (ICM) that forms within N-body/hydrodynamical simulations of galaxy clusters in a \LambdaCDM cosmology. When radiative cooling and a simple...
XMM Cluster Survey: X-ray source identification using the Sloan Digital Sky Survey (2004)
Land, Kate R., Nichol, Robert C., Davidson, Michael, Sabirli, Kivanc, Romer, A. Kathy, Liddle, Andrew R., ...
[ABRIDGED] The XMM Cluster Survey (XCS) is predicted to detect thousands of clusters observed serendipitously in XMM-Newton pointings. We investigate automating optical follow-up of cluster...
Rowley, David R., Thomas, Peter A., Kay, Scott T.
We investigate the growth over time of 20 massive (> 3 keV) clusters in a hydrodynamical simulation of the LambdaCDM cosmology with radiative cooling. The clusters show a variety of formation...
The entropy distribution in clusters: evidence of feedback? (2003)
The entropy of the intracluster medium at large radii has been shown recently to deviate from the self-similar scaling with temperature. Using N-body/hydrodynamic simulations of the LCDM cosmology,...
Da Silva, Antonio C., Kay, Scott T., Liddle, Andrew R., Thomas, Peter A.
The Sunyaev-Zel'dovich effect is a powerful new tool for finding and studying clusters at high redshift, particularly in combination with their X-ray properties. In this paper we quantify the...
Viana, Pedro T P, Kay, Scott T, Liddle, Andrew R, Muanwong, Orrarujee, Thomas, Peter A
The amplitude of density perturbations, for the currently-favoured LambdaCDM cosmology, is constrained using the observed properties of galaxy clusters. The catalogue used is that of Ikebe et al....
The impact of galaxy formation on X-ray groups (2002)
Kay, Scott T., Thomas, Peter A., Theuns, Tom
Using hydrodynamical simulations of the LCDM cosmology, that include both radiative cooling and a phenomenological model for star formation and supernovae feedback, we investigate the impact of...
Simulated X-ray Cluster Temperature Maps (2002)
Onuora, Lesley I., Kay, Scott T., Thomas, Peter A.
Temperature maps are presented of the 9 largest clusters in the mock catalogues of Muanwong et al. for both the Preheating and Radiative models. The maps show that clusters are not smooth,...
The Effect of Cooling and Preheating on the X-ray Properties of Clusters of Galaxies (2002)
Muanwong, Orrarujee, Thomas, Peter A., Kay, Scott T., Pearce, Frazer R.
We calculate X-ray properties of present-day galaxy clusters from hydrodynamical cosmological simulations of the LCDM cosmology and compare these with recent X-ray observations. Results from three...
Can simulations reproduce the observed temperature-mass relation for clusters of galaxies? (2001)
Thomas, Peter A., Muanwong, Orrarujee, Kay, Scott T., Liddle, Andrew R.
It has become increasingly apparent that traditional hydrodynamical simulations of galaxy clusters are unable to reproduce the observed properties of galaxy clusters, in particular overpredicting the...
The impact of cooling and pre-heating on the Sunyaev-Zel'dovich effect (2001)
Da Silva, Antonio C, Kay, Scott T, Liddle, Andrew R, Thomas, Peter A, Pearce, Frazer R, Barbosa, Domingos
We use hydrodynamical simulations to assess the impact of radiative cooling and `pre-heating' on predictions for the Sunyaev--Zel'dovich (SZ) effect. Cooling significantly reduces both the mean SZ...
Kay, Scott T., Pearce, Frazer R., Frenk, Carlos S., Jenkins, Adrian
We investigate phenomenological models of star formation and supernova feedback in N-body/SPH simulations of galaxy formation. First, we compare different prescriptions in the literature for turning...
Kay, Scott T, Liddle, Andrew R, Thomas, Peter A
We use the billion-particle Hubble Volume simulations to make statistical predictions for the distribution of galaxy clusters that will be observed by the Planck Surveyor satellite through their...
Parameter Tests Within Cosmological Simulations of Galaxy Formation (1999)
Kay, Scott T., Pearce, F. R., Jenkins, A., Frenk, C. S., White, S. D. M., Thomas, P. A., ...
Numerical simulations of galaxy formation require a number of parameters. Some of these are intrinsic to the numerical integration scheme (eg the timestep), while others describe the physical model...
Measuring \Omega_0 from the Entropy Evolution of Clusters (1998)
Kay, Scott T., Bower, Richard G.
In this paper, we have extended the entropy-driven model of cluster evolution developed by Bower (1997) in order to be able to predict the evolution of galaxy clusters for a range of cosmological...