English
Related papers

Related papers: Dynamical mass inference of galaxy clusters with n…

200 papers

The distortion of images of faint, high-redshift galaxies by light deflection at foreground clusters of galaxies can be used to determine the (projected) mass distribution of the clusters. In the case of strong distortions, which lead to…

Astrophysics · Physics 2007-05-23 Peter Schneider , Carolin Seitz

We investigate the accuracy requirements for field-level inference of cluster and void masses using data from galaxy surveys. We introduce a two-step framework that takes advantage of the fact that cluster masses are determined by flows on…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-09 Stephen Stopyra , Hiranya V. Peiris , Andrew Pontzen , Jens Jasche , Guilhem Lavaux

Large amounts of deep optical images will be available in the near future, allowing statistically significant studies of low surface brightness structures such as intracluster light (ICL) in galaxy clusters. The detection of these…

Astrophysics of Galaxies · Physics 2021-05-12 A. Ellien , E. Slezak , N. Martinet , F. Durret , C. Adami , R. Gavazzi , C. R. Rabaça , C. Da Rocha , D. N. Epitácio Pereira

We study the assembly of globular clusters (GCs) in 9 galaxy clusters using the cosmological simulation Illustris. GCs are tagged to individual galaxies at their infall time. The tidal removal of GCs from their galaxies and the distribution…

Astrophysics of Galaxies · Physics 2020-03-04 Felipe Ramos-Almendares , Laura V. Sales , Mario G. Abadi , Jessica E. Doppel , Hernan Muriel , Eric W. Peng

Currently, density-based clustering algorithms are widely applied because they can detect clusters with arbitrary shapes. However, they perform poorly in measuring global density, determining reasonable cluster centers or structures,…

Machine Learning · Computer Science 2023-11-02 Mingjie Cai , Zhishan Wu , Qingguo Li , Feng Xu , Jie Zhou

This paper describes the incremental behaviours of Density based clustering. It specially focuses on the Density Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm and its incremental approach.DBSCAN relies on a density…

Databases · Computer Science 2014-06-19 Sanjay Chakraborty , N. K. Nagwani

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

The mass distribution of galaxy clusters can be determined from the study of the projected phase-space distribution of cluster galaxies. The main advantage of this method as compared to others, is that it allows determination of cluster…

Astrophysics · Physics 2016-08-30 Andrea Biviano

The outskirts of galaxy clusters present a promising avenue for constraining cluster masses in a way that is robust to the impact of baryonic physics. We assess the accuracy to which the cluster infall regions can be used to for cluster…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-25 Connor Sweeney , Eduardo Rozo

Peculiar velocity surveys have non-uniform spatial distributions of tracers, so that the bulk flow estimated from them does not correspond to that of a simple volume such as a sphere. Thus bulk flow estimates are generally not strictly…

Astrophysics · Physics 2010-11-24 Richard Watkins , Hume A. Feldman , Michael J. Hudson

The surface mass density of a cluster of galaxies, and thus its total mass, can be estimated from its lens magnification. The magnification can be determined from the variation in number counts of its background galaxies. In the weak…

Astrophysics · Physics 2009-10-30 Eelco van Kampen

This work presents an unsupervised deep discriminant analysis for clustering. The method is based on deep neural networks and aims to minimize the intra-cluster discrepancy and maximize the inter-cluster discrepancy in an unsupervised…

Machine Learning · Computer Science 2022-06-13 Jinyu Cai , Wenzhong Guo , Jicong Fan

The intracluster medium (ICM) records the history of galaxy clusters through its complex dynamical properties. To effectively interpret these properties, robust methods are needed to compare observational data with theoretical models. We…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-20 Efrain Gatuzz

Being able to distinguish between galaxies that have recently undergone major merger events, or are experiencing intense star formation, is crucial for making progress in our understanding of the formation and evolution of galaxies. As…

Astrophysics of Galaxies · Physics 2022-06-01 Leonardo Ferreira , Christopher J. Conselice , Ulrike Kuchner , Clar-Bríd Tohill

Using the intuition that out-of-distribution data have lower likelihoods, a common approach for out-of-distribution detection involves estimating the underlying data distribution. Normalizing flows are likelihood-based generative models…

Machine Learning · Computer Science 2025-01-30 Seyedeh Fatemeh Razavi , Mohammad Mahdi Mehmanchi , Reshad Hosseini , Mostafa Tavassolipour

Identification of the clusters from an unlabeled data set is one of the most important problems in Unsupervised Machine Learning. The state of the art clustering algorithms are based on either the statistical properties or the geometric…

Machine Learning · Computer Science 2018-01-04 Sambarta Dasgupta , Keivan Ebrahimi , Umesh Vaidya

We present a deep machine learning (ML) approach to constraining cosmological parameters with multi-wavelength observations of galaxy clusters. The ML approach has two components: an encoder that builds a compressed representation of each…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 Michelle Ntampaka , Alexey Vikhlinin

We have derived the mean proper motions and space velocities of 154 Galactic globular clusters and the velocity dispersion profiles of 141 globular clusters based on a combination of Gaia DR2 proper motions with ground-based line-of-sight…

Astrophysics of Galaxies · Physics 2018-11-28 H. Baumgardt , M. Hilker , A. Sollima , A. Bellini

In this review, we describe our current understanding of cluster formation: from the general picture of collapse from initial density fluctuations in an expanding Universe to detailed simulations of cluster formation including the effects…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Andrey Kravtsov , Stefano Borgani

We constrain the internal dynamics of a stack of 10 clusters from the GCLASS survey at 0.87<z<1.34. We determine the stack cluster mass profile M(r) using the MAMPOSSt algorithm of Mamon et al., the velocity anisotropy profile beta(r) from…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-12 A. Biviano , R. F. J. van der Burg , A. Muzzin , B. Sartoris , G. Wilson , H. K. C. Yee