English
Related papers

Related papers: Clusterix 2.0. A Virtual Observatory tool to estim…

200 papers

ClusterPyXT is a new software pipeline to generate spectral temperature, X-ray surface brightness, pressure, and density maps from X-ray observations of galaxy clusters. These data products help elucidate the physics of processes occurring…

High Energy Astrophysical Phenomena · Physics 2019-06-07 Brian Alden , Eric J. Hallman , David Rapetti , Jack O. Burns , Abhirup Datta

Most convex and nonconvex clustering algorithms come with one crucial parameter: the $k$ in $k$-means. To this day, there is not one generally accepted way to accurately determine this parameter. Popular methods are simple yet theoretically…

Machine Learning · Computer Science 2021-08-04 Sibylle Hess , Wouter Duivesteijn

Robust galaxy cluster mass estimates are fundamental for constraining cosmological parameters from counts. For this reason, it is essential to search for tracers that, independent of the cluster's dynamical state, have a small intrinsic…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-19 Lia Doubrawa , Eduardo S. Cypriano , Alexis Finoguenov , Paulo A. A. Lopes , Matteo Maturi , Anthony H. Gonzalez , Renato Dupke

We introduce a new effective strategy to assign group and cluster membership probabilities $P_{mem}$ to galaxies using photometric redshift information. Large dynamical ranges both in halo mass and cosmic time are considered. The method…

Cosmology and Nongalactic Astrophysics · Physics 2016-11-09 Gianluca Castignani , Christophe Benoist

Clustering is an essential data mining tool that aims to discover inherent cluster structure in data. For most applications, applying clustering is only appropriate when cluster structure is present. As such, the study of clusterability,…

Machine Learning · Statistics 2018-10-30 A. Adolfsson , M. Ackerman , N. C. Brownstein

This short document illustrates QLUSTER: a toy model for populations of binary black holes in dense astrophysical environments. QLUSTER is a simple tool to investigate the occurrence and properties of hierarchical black-hole mergers…

High Energy Astrophysical Phenomena · Physics 2023-11-30 Davide Gerosa , Matthew Mould

Star clusters provide an excellent opportunity to study the role of environment on determining the frequencies of short period planets. They provide a large sample of stars which can be imaged simultaneously, with a common distance, age and…

Astrophysics · Physics 2007-10-01 David T. F. Weldrake

We introduce a modified model of random walk, and then develop two novel clustering algorithms based on it. In the algorithms, each data point in a dataset is considered as a particle which can move at random in space according to the…

Machine Learning · Computer Science 2008-10-31 Qiang Li , Yan He , Jing-ping Jiang

In this paper, we present a cluster algorithm for the simulation of hard spheres and related systems. In this algorithm, a copy of the configuration is rotated with respect to a randomly chosen pivot point. The two systems are then…

Statistical Mechanics · Physics 2008-02-03 Christophe Dress , Werner Krauth

Membership analysis is an important tool for studying star clusters. There are various approaches to membership determination, including supervised and unsupervised machine learning (ML) methods. We perform membership analysis using the…

Astrophysics of Galaxies · Physics 2024-09-25 A. Bissekenov , M. Kalambay , E. Abdikamalov , X. Pang , P. Berczik , B. Shukirgaliyev

In this work we present a method to identify possible members of globular clusters using data from Gaia DR2. The method consists of two stages: the first one based on a clustering algorithm, and the second one based on the analysis of the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-07 I. H. Bustos Fierro , J. H. Calderón

Context. Clusters of galaxies are important for cosmology and astrophysics. They may be discovered through either the summed optical/IR radiation originating from their member galaxies or via X-ray emission originating from the hot…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-21 Alexey Mints , Axel Schwope , Simon Rosen , François-Xavier Pineau , Francisco Carrera

With the next-generation Timepix3 hybrid pixel detector, new possibilities and challenges have arisen. The Timepix3 segments active sensor area of 1.98 $cm^2$ into a square matrix of 256 x 256 pixels. In each pixel, the Time of Arrival…

Instrumentation and Detectors · Physics 2019-10-30 Lukáš Meduna , Benedikt Bergmann , Petr Burian , Petr Mánek , Stanislav Pospíšil , Michal Suk

Galaxy clusters constitute powerful cosmological probes thanks to comparisons between observed and simulated clusters. As such Virgo constitutes a formidable source for detailed observations facilitated by its proximity. However, the…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-24 Jenny G. Sorce , Jérémy Blaizot , Yohan Dubois

Many open clusters listed in modern catalogues were initially reported by visual astronomers as apparent overdensities of bright stars. As observational techniques and analysis methods continue to improve, some of them have been shown to be…

Solar and Stellar Astrophysics · Physics 2020-01-27 T. Cantat-Gaudin , F. Anders

Feature selection is a vital technique in machine learning, as it can reduce computational complexity, improve model performance, and mitigate the risk of overfitting. However, the increasing complexity and dimensionality of datasets pose…

Machine Learning · Computer Science 2024-07-24 Yuepeng Chen , Weiping Ding , Hengrong Ju , Jiashuang Huang , Tao Yin

This work considers clustering nodes of a largely incomplete graph. Under the problem setting, only a small amount of queries about the edges can be made, but the entire graph is not observable. This problem finds applications in…

Machine Learning · Computer Science 2021-10-04 Shahana Ibrahim , Xiao Fu

Fast radio transient search algorithms identify signals of interest by iterating and applying a threshold on a set of matched filters. These filters are defined by properties of the transient such as time and dispersion. A real transient…

In many situations it is desirable to identify clusters that differ with respect to only a subset of features. Such clusters may represent homogeneous subgroups of patients with a disease, such as cancer or chronic pain. We define a…

Methodology · Statistics 2014-07-14 Qian Liu , Guanhua Chen , Michael R. Kosorok , Eric Bair

We develop the Blooming Tree Algorithm, a new technique that uses spectroscopic redshift data alone to identify the substructures and the surrounding groups of galaxy clusters, along with their member galaxies. Based on the estimated…

Astrophysics of Galaxies · Physics 2018-06-21 Heng Yu , Antonaldo Diaferio , Ana Laura Serra , Marco Baldi