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The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote
The Acs Virgo Cluster Survey. Xiv. Analysis Of Color-Magnitude Relations In Globular Cluster Systems, Steffen Mieske, Andres Jordan, Patrick Cote
Articles
We examine the correlation between globular cluster (GC) color and magnitude using HST/ACS imaging for a sample of 79 early-type galaxies (−21.7 < MB < −15.2 mag) with accurate surfacebrightness fluctuation distances from the ACS Virgo Cluster Survey. Using the KMM mixture modeling algorithm, we find a highly significant correlation, z ≡ d(g−z) dz = −0.037 ± 0.004, between color and magnitude for the subpopulation of blue GCs in the co-added GC color-magnitude diagram of the three brightest Virgo cluster galaxies (M49, M87 and M60). The sense of the correlation is such that brighter GCs are redder than their fainter counterparts. For the single GC systems of M87 and M60, we find similar correlations; M49 does not appear to show a significant trend. There is no correlation between (g − z) and Mz for GCs belonging to the red subpopulation. The correlation g ≡ d(g−z) dg for the blue subpopulation is much weaker than z. Using Monte Carlo simulations, we attribute this finding to the fact that the blue subpopulation in Mg extends to higher luminosities than does the red subpopulation, which biases the KMM fit results. The highly significant correlation between color and Mz, however, is a real effect: this conclusion is supported by biweight fits to the same color distributions. We identify two environmental dependencies which influence the derived color-magnitude relation: (1) the slope of the color-magnitude relation decreases in significance with decreasing galaxy luminosity, although it remains detectable over the full luminosity range of our sample; and (2) the slope is stronger for GC populations located at smaller galactocentric distances. These characteristics suggest that the observed trend is, at least partially, shaped by external agents. We examine several physical mechanisms that might give rise to the observed color-magnitude relation including: (1) presence of contaminants like super-clusters, stripped galactic nuclei, or ultra-compact dwarfs; (2) accretion of GCs from low-mass galaxies; (3) stochastic effects; (4) the capture of field stars by individual GCs; and (5) GC self-enrichment. Although none of these scenarios offers a fully satisfactory explanation of the observations, we conclude that self-enrichment and field-star capture, or a combination of these processes, offer the most promising means of explaining our observations.
The Huddle/Tangle Hypothesis Of Regional Integration: The Case Of The European Union And Its Enlargement, E. Sanidas
The Huddle/Tangle Hypothesis Of Regional Integration: The Case Of The European Union And Its Enlargement, E. Sanidas
Faculty of Business - Economics Working Papers
Regional integration can be a process that resembles that of a huddle/tangle. Some countries might be more prone or keen or able to integrate than others; however there is no guarantee that this process will be smooth through time. On the contrary, integrating countries seem to hover and spin around some main stronger economically countries and form a tangle. Was there a pattern of integration for the various stages of new countries joining the EU? Was the initial momentum created by the founding countries a situation that has never changed during the last 40 years or so? Is there any …
Mechanisms Underlying The Phenomenon Of Cluster Formation In The Textile/Apparel Industry In Pakistan, Khadija Bari
Mechanisms Underlying The Phenomenon Of Cluster Formation In The Textile/Apparel Industry In Pakistan, Khadija Bari
Business Review
The objective of this study is to analyze the ability of Pakistan’s textile industry to broaden and upgrade its competitive positions in the face of increasing international competition. It suggests a conceptual framework of organisational characteristics influencing the process and formation of clusters. Clusters are a driving force in increasing exports and magnets for attracting foreign investment. The cluster concept represents a new way of thinking about national, state, and city economies, and points to new roles for companies, governments, and other institutions striving to enhance competitiveness. The paper is based on empirical analysis of the organizational characteristics and intra-cluster …
Global Pipelines: Profiling Successful Sme Exporters Within The Australian Wine Industry, D. K. Aylward
Global Pipelines: Profiling Successful Sme Exporters Within The Australian Wine Industry, D. K. Aylward
Faculty of Commerce - Papers (Archive)
Increasingly, entire industry sectors and individual firms are re-orienting their business strategies to align with the demands of rapid globalization. Sustainable export mechanisms are becoming an integral component of these strategies. Small, medium and large firms are focusing more than ever on marketing goals, branding, distribution channels and production quality in order to address the growing opportunities and challenges of this globalization. An industry in which firms are responding effectively to these opportunities and challenges is the Australian wine industry. In terms of export growth, intensity, diversity and sustainability, this industry is increasingly seen as a template for others. Using …
The Noao Fundamental Plane Survey - Iii. Variations In The Stellar Populations Of Red-Sequence Galaxies From The Cluster Core To The Virial Radius, Russell J. S. Smith, Michael J. Hudson, John R. Lucey, Jenica E. Nelan, Gary A. Wegner
The Noao Fundamental Plane Survey - Iii. Variations In The Stellar Populations Of Red-Sequence Galaxies From The Cluster Core To The Virial Radius, Russell J. S. Smith, Michael J. Hudson, John R. Lucey, Jenica E. Nelan, Gary A. Wegner
Dartmouth Scholarship
We analyse absorption line-strength indices for ~3000 red-sequence galaxies in 94 nearby clusters, to investigate systematic variations of their stellar content with location in the host cluster. The data are drawn from the NOAO Fundamental Plane Survey. Our adopted method is a generalization of that introduced by Nelan et al. to determine the global age-mass and metallicity-mass relations from the same survey. We find strong evidence for a change in galaxy properties, at fixed mass, over a range from the cluster centre to the virial radius, R_200. For example, red-sequence galaxies further out in the clusters have weaker Mgb5177 (at …
The Road To Innovation: Experiences In The Australian Wine Industry, D. K. Aylward
The Road To Innovation: Experiences In The Australian Wine Industry, D. K. Aylward
Faculty of Commerce - Papers (Archive)
No abstract provided.
The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic
The Effect Of Small Business Clusters In Prioritising Barriers To E-Commerce Adoption In Regional Smes, Robert Macgregor, Lejla Vrazalic
Faculty of Engineering and Information Sciences - Papers: Part A
This paper presents a study of Swedish regional small businesses which investigated the barriers to E-commerce adoption (amongst other things). The aim of the paper is twofold: to examine the correlation between barriers to E-commerce adoption in order to identify underlying factors: and to determine whether these differ between SMEs that are members of a small business cluster and SMEs that are not. The paper begins by examining the nature of SMEs and identifying features that are unique to SMEs. A discussion of barriers to E-commerce adoption based on previous research is then presented and the barriers are mapped to …
Sme Innovation Within The Australian Wine Industry: A Cluster Analysis, David Aylward, John Glynn
Sme Innovation Within The Australian Wine Industry: A Cluster Analysis, David Aylward, John Glynn
Faculty of Commerce - Papers (Archive)
This paper assesses core innovation activity among SMEs within different levels of cluster development. The aim of the paper, using empirical data from the Australian wine industry, is to demonstrate that innovation levels and activity intensify as an industry cluster develops. By dividing wine clusters into ‘innovative’ (highly developed) and ‘organised’ (less developed) models, the paper uses selected core indicators of innovation activity to explore levels of integration within each model. This integration is examined in the context of Porter’s theory of ‘competitive advantage’, with implications for SMEs in particular, and lessons for industry clusters in general.
Photoionization Of Xenon Clusters, John D. Bozek, Bruce S. Rude, A. L. D. Kilcoyne
Photoionization Of Xenon Clusters, John D. Bozek, Bruce S. Rude, A. L. D. Kilcoyne
US Department of Energy Publications
High resolution photoelectron spectra of xenon clusters of about 100 atoms, measured with photon energies of 20 to 60 eV are reported. Peaks due to the clusters are observed at lower binding energies than the corresponding atomic lines and exhibit different behaviors. The peak associated with the Xe 5p1/2 state at higher binding energy is relatively unchanged with photon energy whereas the Xe 5p3/2 peak changes its shape with increasing photon energy. The change is attributed to differences in the escape depth of the electrons at different kinetic energies and the bulk and surface components of the cluster.
Spin-Polarized Electronic Structure, Arti Kashyap, Renat F. Sabirianov, Sitaram S, Jaswal
Spin-Polarized Electronic Structure, Arti Kashyap, Renat F. Sabirianov, Sitaram S, Jaswal
Physics Faculty Publications
This chapter is devoted to the electronic structure of nanoscale metallic magnets. After an introduction to methods of electronic structure calculations, we review how recent trends translate into the description of magnetic nanostructures. Among the considered structures are nanowires, small particles, surfaces and interfaces, and multilayers, and emphasis is on magnetic properties such as moment and magnetization, interatomic exchange, and anisotropy. One of the goals of computational nanoscience is to calculate physical and chemical properties from first principles. This requires the knowledge of the electronic structures of the materials system in question. The density-functional theory (DFT) makes a huge step …