Related papers: Dynamical Search for Substructures in Galaxy Clust…
We present a new method of analysing and quantifying velocity structure in star forming regions suitable for the rapidly increasing quantity and quality of stellar position-velocity data. The method can be applied to data in any number of…
This document aims at reviewing the different types of clustering algorithms and substructures detection techniques in order to study the spatial and kinematic clustering of stars and detect the gas components in molecular clouds. It is the…
The cluster environment is the site of important transformations in galaxies at a relatively recent cosmological epoch: the galactic morphological types and star formation activity have evolved significantly during the last few Gyrs. How is…
We study the mass distribution of a sample of 24 X-ray bright Abell clusters through weak gravitational lensing. This method is independent of the dynamical state of the galaxy cluster. Hence, by comparing dynamical and lensing mass…
A new method to derive age differences between the various super star clusters observed in starburst galaxies using the two color diagram (B-H) vs (H-K) is presented. This method offers a quick and easy way to differentiate very young and…
Understanding the physical and evolutionary properties of Hot Stellar Systems (HSS) is a major challenge in astronomy. We studied the dataset on 13456 HSS of Misgeld and Hilker (2011) that includes 12763 candidate globular clusters using…
We study the dependence of galaxy properties on the clustercentric radius and the environment attributed to the nearest neighbor galaxy using the SDSS galaxies associated with the Abell galaxy clusters. We find that there exists a…
We present a description of the observations and data reduction procedures for an extensive spectroscopic and multi-band photometric study of nine high redshift, optically-selected cluster candidates. The primary goal of the survey is to…
We summarize the results of recent theoretical work on the dynamical evolution of globular clusters containing primordial binaries. Even a very small initial binary fraction (e.g., 10%) can play a key role in supporting a cluster against…
Complex networks constitute the backbones of many complex systems such as social networks. Detecting the community structure in a complex network is both a challenging and a computationally expensive task. In this paper, we present the…
In a recent publication, the flexion aperture mass statistic was found to provide a robust and effective method by which substructure in galaxy clusters might be mapped. Moreover, we suggested that the masses and mass profile of structures…
The use of galaxy clusters as cosmological probes relies on a detailed understanding of their properties. We aim to update the spectroscopic cluster identification of CODEX by running the spectroscopic group finder on the follow-up…
This paper characterizes hierarchical clustering methods that abide by two previously introduced axioms -- thus, denominated admissible methods -- and proposes tractable algorithms for their implementation. We leverage the fact that, for…
A dynamical analysis of the structure of the clusters of galaxies Abell 119 and Abell 133 is presented, using new redshift data combined with existing data from the literature. We compare our results with those from the X-ray data for these…
Co-clustering simultaneously clusters rows and columns, revealing more fine-grained groups. However, existing co-clustering methods suffer from poor scalability and cannot handle large-scale data. This paper presents a novel and scalable…
In this paper, we introduce Adaptive Cluster Lasso(ACL) method for variable selection in high dimensional sparse regression models with strongly correlated variables. To handle correlated variables, the concept of clustering or grouping…
The Abell 1689 galaxy cluster has recently become a subject of intensive study. Thanks to its intermediate redshift (z=0.183) its mass distribution can be reconstructed using numerous methods including gravitational lensing, galaxy…
Deep clustering has been dominated by flat models, which split a dataset into a predefined number of groups. Although recent methods achieve an extremely high similarity with the ground truth on popular benchmarks, the information contained…
We present an efficient and robust approach for extracting clusters of galaxies from weak lensing survey data and measuring their properties. We use simple, physically-motivated cluster models appropriate for such sparse, noisy data, and…
The strong lensing modelling of gravitational ``rings'' formed around massive galaxies is sensitive to the amplitude of the external shear and convergence produced by nearby mass condensations. In current wide field surveys, it is now…