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Related papers: Multivariate Evolutionary Analyses in Astrophysics

200 papers

It is possible to borrow from a topic of biology called phylogenetic systematics, concepts and tools for a logical and objective classification of galaxies. It is based on observable properties of objects - characters - either qualitative…

Astrophysics · Physics 2009-11-07 Didier Fraix-Burnet , Philippe Choler , Emmanuel J. P. Douzery

I discuss the chemical and spectrophotometric evolution of galaxies over cosmological timescales and present a first attempt to treat both aspects in a chemically consistent way. In our evolutionary synthesis approach, we account for the…

Astrophysics · Physics 2007-05-23 U. Fritze-v. Alvensleben

The colour bimodality of galaxies provides an empirical basis for theories of galaxy evolution. However, the balance of processes that begets this bimodality has not yet been constrained. A more detailed view of the galaxy population is…

Measuring the evolution in the clustering of galaxies over a large redshift range is a challenging problem. For a two-dimensional galaxy catalog, however, we can measure the galaxy-galaxy angular correlation function which provides…

Astrophysics · Physics 2009-10-31 Robert J. Brunner , Andrew J. Connolly , Alex S. Szalay

The combination of measurements of the local abundance of rich clusters of galaxies and its evolution to higher redshift offers the possibility of a direct measurement of $\Omega_0$ with little contribution from other cosmological…

We present two different projects. The first one is related to the development of a semi-analytic model to follow the formation, the evolution and chemical enrichment of cluster galaxies in a hierarchical dark matter model. The second…

Astrophysics · Physics 2007-05-23 Gabriella De Lucia , Guinevere Kauffmann , Simon D. M. White

Some factors connecting the evolutionary histories of galaxies with the characteristics of their cluster systems are reviewed. Unanswered questions include: How is one to understand the observation that some globular cluster systems have…

Astrophysics · Physics 2007-05-23 Sidney van den Bergh

The studies of the evolution of galaxies in Galaxy Clusters have as a traditional complication the difficulty in establishing cluster membership of those sources detected in the field of view. The determination of spectroscopic redshifts…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Ricardo Perez-Martinez , Miguel Sanchez-Portal , Jordi Cepa , Angel Bongiovanni , Ana Perez Garcia

An introduction is given to projects investigating galaxy evolution quantitatively by spectroscopic observations of very distant galaxies that have weak apparent brightnesses and small sizes as it is feasible with 10m-class telescopes like…

Astrophysics · Physics 2007-05-23 Bodo L. Ziegler

In many practical applications of clustering, the objects to be clustered evolve over time, and a clustering result is desired at each time step. In such applications, evolutionary clustering typically outperforms traditional static…

Machine Learning · Computer Science 2015-03-19 Kevin S. Xu , Mark Kliger , Alfred O. Hero

Stars are fossils that retain the history of their host galaxies. Elements heavier than helium are created inside stars and are ejected when they die. From the spatial distribution of elements in galaxies, it is therefore possible to…

Astrophysics of Galaxies · Physics 2023-04-27 Chiaki Kobayashi , Philip Taylor

We study the evolution of galaxies in clusters by the analysis of a sample of about 3000 galaxies, members of 59 clusters from the ESO Nearby Abell Cluster Survey (ENACS). We distinguish four cluster galaxy populations, based on their…

Astrophysics · Physics 2007-05-23 A. Biviano , P. Katgert , T. Thomas , A. Mazure

Star clusters are studied widely both as benchmarks for stellar evolution models and in their own right. Cluster age and mass distributions within galaxies are probes of star formation histories, and of cluster formation and disruption…

Solar and Stellar Astrophysics · Physics 2015-05-18 Morgan Fouesneau , Ariane Lançon

This talk investigates the formation of early-type galaxies from a deliberately observational view point. I begin by reviewing the conclusions that can be reached by comparing the detailed properties of galaxies in present-day clusters,…

Astrophysics · Physics 2007-05-23 Richard G. Bower , Ale Terlevich , Tadayuki Kodama , Nelson Caldwell

Star clusters and their stellar populations play a significant role in the context of galaxy evolution, across space (from local to high redshift) and time (from currently forming to fossil remnants). We are now within reach of answering a…

Astrophysics of Galaxies · Physics 2015-05-14 Richard de Grijs

In Astrophysics, the identification of candidate Globular Clusters through deep, wide-field, single band HST images, is a typical data analytics problem, where methods based on Machine Learning have revealed a high efficiency and…

Instrumentation and Methods for Astrophysics · Physics 2017-10-12 Giuseppe Angora , Massimo Brescia , Giuseppe Riccio , Stefano Cavuoti , Maurizio Paolillo , Thomas H. Puzia

In hierarchical cosmologies the evolution of galaxy clustering depends both on cosmological quantities such as Omega and Lambda, which determine how dark matter halos form and evolve, and on the physical processes - cooling, star formation…

We investigate the properties and evolution of star particles in two simulations of isolated spiral galaxies, and two galaxies from cosmological simulations. Unlike previous numerical work, where typically each star particle represents one…

We discuss the theoretical interpretation of observational data concerning the clustering of galaxies at high redshifts. Building on the theoretical machinery developed by Matarrese et al. (1997), we make detailed quantitative predictions…

Astrophysics · Physics 2009-10-30 Lauro Moscardini , Peter Coles , Francesco Lucchin , Sabino Matarrese

Cluster analysis methods seek to partition a data set into homogeneous subgroups. It is useful in a wide variety of applications, including document processing and modern genetics. Conventional clustering methods are unsupervised, meaning…

Methodology · Statistics 2014-07-11 Eric Bair