English
Related papers

Related papers: Evolution of Cluster Morphology: X-ray data vs. CD…

200 papers

We analyse Chandra X-ray Observatory observations of a set of galaxy clusters selected by the South Pole Telescope using a new publicly-available forward-modelling projection code, MBProj2, assuming hydrostatic equilibrium. By fitting a…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-20 J. S. Sanders , A. C. Fabian , H. R. Russell , S. A. Walker

Surface brightness evolution has been detected in elliptical galaxies (consistent with passive evolution models of old stellar populations) and in disk galaxies (presumably due to enhanced star-formation rates). The rates of evolution in…

Astrophysics · Physics 2007-05-23 David Schade

We present a novel probabilistic clustering model for objects that are represented via pairwise distances and observed at different time points. The proposed method utilizes the information given by adjacent time points to find the…

Machine Learning · Computer Science 2015-04-16 Julia E. Vogt , Marius Kloft , Stefan Stark , Sudhir S. Raman , Sandhya Prabhakaran , Volker Roth , Gunnar Rätsch

Whether the X-ray luminosities of clusters of galaxies evolve has been a contentious issue for over ten years. However, the data available to address this issue have improved dramatically as cluster surveys from the ROSAT archive near…

Astrophysics · Physics 2007-05-23 J. Patrick Henry

We investigate the evolution of clusters of galaxies in a sample of distant clusters with redshifts between 0.3 and 1.0. We show the abilities and limitations of combined ROSAT and ASCA data to draw cosmological conclusions. For the first…

Astrophysics · Physics 2007-05-23 Sabine Schindler

Understanding the formation and evolution of young star clusters requires quantitative statistical measures of their structure. We investigate the structures of observed and modelled star-forming clusters. By considering the different…

Astrophysics · Physics 2007-05-23 S. Schmeja , R. S. Klessen

We compare the distribution of internal velocity dispersions of galaxy clusters for an observational sample to those obtained from a set of N-body simulations of seven COBE-normalised cosmological scenarios: the standard CDM (SCDM) and a…

Astrophysics · Physics 2009-10-30 S. Borgani , A. Gardini , M. Girardi , S. Gottloeber

The study of their morphological coherence allows us to obtain a better understanding of the morphological evolution of open clusters. We employed the ellipsoid fitting method to delineate the 3D spatial structure of the sample clusters…

Astrophysics of Galaxies · Physics 2024-07-24 Qingshun Hu , Yu Zhang , Songmei Qin , Jing Zhong , Li Chen , Yangping Luo

We study the substructure statistics of a representative sample of galaxy clusters by means of two currently popular substructure characterisation methods, power ratios and centroid shifts. We use the 31 clusters from the REXCESS sample,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 H. Boehringer , G. W. Pratt , M. Arnaud , S. Borgani , J. H. Croston , T. J. Ponman , S. Ameglio , R. F. Temple , K. Dolag

Most generative models for clustering implicitly assume that the number of data points in each cluster grows linearly with the total number of data points. Finite mixture models, Dirichlet process mixture models, and Pitman--Yor process…

Methodology · Statistics 2015-12-03 Jeffrey Miller , Brenda Betancourt , Abbas Zaidi , Hanna Wallach , Rebecca C. Steorts

We report measurements of the cluster X-ray luminosity function out to z=0.8 based on the final sample of 201 galaxy systems from the 160 Square Degree ROSAT Cluster Survey. There is little evidence for any measurable change in cluster…

We examine how the Sunyaev-Zel'dovich (SZ) effect of clusters can probe $\Omega_{o}$. Using self-consistent models of X-ray clusters in the context of hierarchical models of structure formation, we show that both the mean Compton {\it y}…

Astrophysics · Physics 2016-08-30 Domingos Barbosa , James G. Bartlett , Alain Blanchard , Jamila Oukbir

We study the observed evolution of galaxy clustering as a function of redshift. We find that the clustering of galaxies decreases as we go from observations of the local Universe to $z \sim 2$. On the other hand, clustering of the Lyman…

Astrophysics · Physics 2009-10-31 M. Magliocchetti , J. S. Bagla , S. J. Maddox , O. Lahav

We have used the Advanced Camera for Surveys (ACS) on the HST to obtain optical imaging of a sample of 8 galaxy clusters in the redshift range 0.8 < z < 1.3. The ACS data provides accurate photometry and the ACS high angular resolution…

We present a large X-ray selected serendipitous cluster survey based on a novel joint analysis of archival Chandra and XMM-Newton data. The survey provides enough depth to reach clusters of flux of $\approx 10^{-14} {ergs} {cm}^{-2}…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 J. R. Peterson , J. G. Jernigan , R. R. Gupta , J. Bankert , S. M. Kahn

The evolution of the X-ray luminosity function of clusters of galaxies has been measured to z=0.9 using over 150 X-ray selected clusters discovered in the WARPS survey. We find no evidence for evolution of the luminosity function at any…

Astrophysics · Physics 2007-05-23 L. R. Jones , H. Ebeling , C. Scharf , E. Perlman , D. Horner , B. W. Fairley , S. Ellis , G. Wegner , M. Malkan

Results from a large set of hydrodynamical SPH simulations of galaxy clusters in a flat LCDM cosmology are used to investigate cluster X-ray properties. The physical modeling of the gas includes radiative cooling, star formation, energy…

Astrophysics · Physics 2007-05-23 R. Valdarnini

We use two high resolution CDM simulations to show that (i) when clusters of galaxies form the infall pattern of matter is not random but shows clear features which are correlated in time; (ii) in addition, the infall patterns are…

Astrophysics · Physics 2007-05-23 J. M. Colberg , S. D. M. White , A. Jenkins , F. R. Pearce

We describe and test a method to quantitatively classify clusters of galaxies according to their projected morphologies. This method will be subsequently used to place constraints on cosmological parameters ($\Omega$ and the power spectrum…

Astrophysics · Physics 2009-10-28 David A. Buote , John C. Tsai

We quantify the evolution of matter and galaxy clustering in cosmological hydrodynamical simulations via correlation and bias functions of matter and galaxies. We use simulations TNG100 and TNG300 with epochs from $z=5$ to $z=0$. We…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-14 Jaan Einasto , Gert Hütsi , Lauri-Juhan Liivamägi , Changbom Park , Juhan Kim , Istval Szapudi , Maret Einasto
‹ Prev 1 4 5 6 7 8 10 Next ›