English
Related papers

Related papers: Using X-Ray Morphological Parameters to Strengthen…

200 papers

The possibility to constrain cosmological parameters from galaxy surveys using field-level machine learning methods that bypass traditional summary statistics analyses, depends crucially on our ability to generate simulated training sets.…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-11 Iñigo Sáez-Casares , Matteo Calabrese , Davide Bianchi , Marina S. Cagliari , Marco Chiarenza , Jean-Marc Christille , Luigi Guzzo

We report weak-lensing masses for 51 of the most X-ray luminous galaxy clusters known. This cluster sample, introduced earlier in this series of papers, spans redshifts 0.15 < z_cl < 0.7, and is well suited to calibrate mass proxies for…

Nowadays, Machine Learning techniques offer fast and efficient solutions for classification problems that would require intensive computational resources via traditional methods. We examine the use of a supervised Random Forest to classify…

Astrophysics of Galaxies · Physics 2022-06-22 I. Marini , S. Borgani , A. Saro , G. Murante , G. L. Granato , C. Ragone-Figueroa , G. Taffoni

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 use cosmological gas dynamic simulations to investigate the accuracy of galaxy cluster mass estimates based on X-ray observations. The experiments follow the formation of clusters in different cosmological models and include the effects…

Astrophysics · Physics 2009-10-28 August E. Evrard , Christopher A. Metzler , Julio F. Navarro

Galaxy clusters are one of the most powerful probes to study extensions of General Relativity and the Standard Cosmological Model. Upcoming surveys like the Vera Rubin Observatory's Legacy Survey of Space and Time are expected to…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-19 Markus Michael Rau , Florian Kéruzoré , Nesar Ramachandra , Lindsey Bleem

Precise determination of galaxy cluster masses is crucial for establishing reliable mass-observable scaling relations in cluster cosmology. We employ graph neural networks (GNNs) to estimate galaxy cluster masses from radially sampled…

Cosmology and Nongalactic Astrophysics · Physics 2026-01-14 Asif Iqbal , Subhabrata Majumdar , Elena Rasia , Gabriel W. Pratt , Daniel de Andres , Jean-Baptiste Melin , Weiguang Cui

We discuss the measurements of the galaxy cluster mass functions at z=~0.05 and z=~0.5 using high-quality Chandra observations of samples derived from the ROSAT PSPC All-Sky and 400deg^2 surveys. We provide a full reference for the data…

We propose a random forest (RF) machine learning approach to determine the accreted stellar mass fractions ($f_\mathrm{acc}$) of central galaxies, based on various dark matter halo and galaxy features. The RF is trained and tested using…

Astrophysics of Galaxies · Physics 2022-06-14 Rui Shi , Wenting Wang , Zhaozhou Li , Jiaxin Han , Jingjing Shi , Vicente Rodriguez-Gomez , Yingjie Peng , Qingyang Li

X-ray observations of galaxy clusters potentially provide powerful cosmological probes if systematics due to our incomplete knowledge of the intracluster medium (ICM) physics are understood and controlled. In this paper, we present mock…

Astrophysics · Physics 2008-11-26 Daisuke Nagai , Alexey Vikhlinin , Andrey V. Kravtsov

Forthcoming large galaxy cluster surveys will yield tight constraints on cosmological models. It has been shown that in an idealized survey, containing > 10,000 clusters, statistical errors on dark energy and other cosmological parameters…

Astrophysics · Physics 2008-11-26 Joshua D. Younger , Zoltan Haiman , Greg L. Bryan , Sheng Wang

X-ray selected surveys of clusters of galaxies have been reported to contain more regular cool core clusters compared to samples selected using the Sunyaev-Zel'dovich (SZ) effect. Morphology population studies on X-ray selected clusters…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-18 J. S. Sanders , Y. E. Bahar , E. Bulbul , N. Clerc , J. Comparat , M. Kluge , A. Liu , N. Malavasi , M. E. Ramos-Ceja , T. H. Reiprich , F. Balzer , V. Ghirardini , F. Pacaud , X. Zhang

We present a modern machine learning approach for cluster dynamical mass measurements that is a factor of two improvement over using a conventional scaling relation. Different methods are tested against a mock cluster catalog constructed…

Cosmology and Nongalactic Astrophysics · Physics 2021-01-15 Michelle Ntampaka , Hy Trac , Danica J. Sutherland , Nicholas Battaglia , Barnabas Poczos , Jeff Schneider

This article is the second in a series in which we perform an extensive comparison of various galaxy-based cluster mass estimation techniques that utilise the positions, velocities and colours of galaxies. Our aim is to quantify the…

We present the results of a simple but robust morphological classification of a statis- tically complete sample of 108 of the most X-ray luminous clusters at 0.15 < z < 0.7 observed with Chandra. Our aims are to (a) identify the most…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Andrew W. Mann , Harald Ebeling

We present a theoretical model which aims at predicting the clustering properties of X-ray clusters in flux-limited surveys for different cosmological scenarios. The model uses the theoretical and empirical relations between mass,…

We investigate the importances of various dynamical features in predicting the dynamical state (DS) of galaxy clusters, based on the Random Forest (RF) machine learning approach. We use a large sample of galaxy clusters from the Three…

Cosmology and Nongalactic Astrophysics · Physics 2022-07-14 Qingyang Li , Jiaxin Han , Wenting Wang , Weiguang Cui , Federico De Luca , Xiaohu Yang , Yanrui Zhou , Rui Shi

We forecast the potential of the forthcoming X-ray galaxy-cluster survey with eROSITA to constrain dark-energy models. We focus on spatially-flat cosmological scenarios with either constant or time-dependent dark-energy equation-of-state…

Cosmology and Nongalactic Astrophysics · Physics 2018-08-29 Annalisa Pillepich , Thomas H. Reiprich , Cristiano Porciani , Katharina Borm , Andrea Merloni

Morphology is often used to infer the state of relaxation of galaxy clusters. The regularity, symmetry, and degree to which a cluster is centrally concentrated inform quantitative measures of cluster morphology. The Cluster Lensing and…

X-ray images of galaxy clusters often show disturbed structures that are indication of cluster mergers. As a complementary to our previous work on dynamical state of 964 clusters observed by the Chandra, we process the X-ray images for 1308…

Astrophysics of Galaxies · Physics 2025-09-29 Z. S. Yuan , J. L. Han , Z. L. Wen