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Related papers: Multivariate Evolutionary Analyses in Astrophysics

200 papers

We present a new method for dealing with geometrical selection effects in galaxy surveys while using a multifractal framework. The power of multifractal analysis lies in its connection to higher order moments, in that it not only probes…

Astrophysics · Physics 2010-11-11 Cristiano Sabiu , Luis Teodoro , Martin Hendry

Evolutionary clustering aims at capturing the temporal evolution of clusters. This issue is particularly important in the context of social media data that are naturally temporally driven. In this paper, we propose a new probabilistic…

Information Retrieval · Computer Science 2016-01-12 Young-Min Kim , Julien Velcin , Stéphane Bonnevay , Marian-Andrei Rizoiu

During this last decade our knowledge of the evolutionary properties of stars has significantly improved. This result has been achieved thanks to our improved understanding of the physical behavior of stellar matter in the thermal regimes…

Solar and Stellar Astrophysics · Physics 2015-05-14 Santi Cassisi

Cluster analysis is the distribution of objects into different groups or more precisely the partitioning of a data set into subsets (clusters) so that the data in subsets share some common trait according to some distance measure. Unlike…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-17 Tuli De , Didier Fraix-Burnet , Asis Kumar Chattopadhyay

The study of galaxies has changed dramatically over the past few decades with the advent of large-scale astronomical surveys. These large collaborative efforts have made available high-quality imaging and spectroscopy of hundreds of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Chris Lintott , Karen Masters , Brooke Simmons , Steven Bamford , Sugata Kaviraj

We study the observed evolution of galaxy clustering as a function of redshift. We find that the clustering of galaxies decreases as we go from observations of the local Universe to $z \sim 2$. On the other hand, clustering of the Lyman…

Astrophysics · Physics 2009-10-31 M. Magliocchetti , J. S. Bagla , S. J. Maddox , O. Lahav

We are briefly introducing the most important ingredients to study galactic evolution. In particular the roles of star formation, nucleosynthesis and gas flows. Then we are discussing the two different approaches to galactic evolution: the…

Astrophysics · Physics 2009-11-07 Francesca Matteucci

We study the evolution of embedded clusters. The equations of motion of the stars in the cluster are solved by direct N-body integration while taking the effects of stellar evolution and the hydrodynamics of the natal gas content into…

Solar and Stellar Astrophysics · Physics 2015-06-03 F. I. Pelupessy , S. Portegies Zwart

Advances in extragalactic astronomy have prompted the development of increasingly realistic models which aim to describe the formation and evolution of galaxies. We review the philosophy behind one such technique, called semi-analytic…

Astrophysics · Physics 2009-11-07 C. M. Baugh , A. J. Benson , S. Cole , C. S. Frenk , C. Lacey

Galactic globular clusters are old, dense star systems typically containing 10\super{4}--10\super{7} stars. As an old population of stars, globular clusters contain many collapsed and degenerate objects. As a dense population of stars,…

Solar and Stellar Astrophysics · Physics 2015-05-30 Matthew J. Benacquista , Jonathan M. B. Downing

Clusters of galaxies are important laboratories for understanding both galaxy evolution and constraining cosmological quantities. Any analysis of clusters, however, is best done when one can reliably determine which galaxies are members of…

Astrophysics · Physics 2009-10-31 R. J. Brunner , L. M. Lubin

Number counts and redshift distribution of gravitational arcs are computed in the field of massive clusters of galaxies to probe the universe at high redshift. Using an accurate modelling for the cluster mass distribution and a model for…

Astrophysics · Physics 2007-05-23 J. Bezecourt

We propose a statistical method for clustering of multivariate longitudinal data into homogeneous groups. This method relies on a time-varying extension on the classical K-means algorithm, where a multivariate vector autoregressive model is…

Methodology · Statistics 2014-04-25 Antonello Maruotti , Maurizio Vichi

We review several aspects of clusters of galaxies and their application to cosmology. We present first results of numerical simulations of the dynamics of the intra-cluster gas and of different interaction processes between cluster galaxies…

Astrophysics · Physics 2017-11-01 Sabine Schindler

In the last years many studies examined the consistency of students' answers in a variety of contexts. Some of these papers tried to develop more detailed models of the consistency of students' reasoning, or to subdivide a sample of…

Physics Education · Physics 2017-08-17 Onofrio Rosario Battaglia , Benedetto Di Paola , Claudio Fazio

Identification of disease subtypes and corresponding biomarkers can substantially improve clinical diagnosis and treatment selection. Discovering these subtypes in noisy, high dimensional biomedical data is often impossible for humans and…

Quantitative Methods · Quantitative Biology 2020-05-18 Marc-Andre Schulz , Matt Chapman-Rounds , Manisha Verma , Danilo Bzdok , Konstantinos Georgatzis

It appears that the dynamical status of clusters and groups of galaxies is related to the large-scale structure of the Universe. A few interesting trends have been established: (1) The Cluster Substructure - Alignment Connection, by which…

Astrophysics · Physics 2009-11-10 Manolis Plionis

A simple chemical enrichment model for cluster early-type galaxies is described in which the mechanisms considered in the evolutionary model are infall of primordial gas, outflows and a possible variation in the star formation efficiency.…

Astrophysics · Physics 2009-10-31 I. Ferreras , J. Silk

Galaxy physical properties are influenced by their environments, but the processes responsible for mass and environmental quenching and structural transformations remain debated. Galaxy clusters are ideal laboratories for investigating…

As a tool to interpret nearby and high redshift galaxy data from optical to K-band we present our chemically consistent spectrophotometric evolutionary synthesis models. These models take into account the increasing initial metallicity of…

Astrophysics · Physics 2009-10-31 C. S. Möller , U. Fritze-v. Alvensleben , K. J. Fricke , D. Calzetti