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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Turbulent mixing of chemical elements in galaxies

Pan, Liubin. January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2008. / Vita. Includes bibliographical references.
72

Tidal structure in Galactic satellites /

Coleman, Matthew Grant. January 2004 (has links)
Thesis (Ph.D.)--Australian National University, 2004.
73

The structure of the Coma cluster of galaxies

Noonan, Thomas Wyatt. January 1961 (has links)
Thesis (Ph. D.)--California Institute of Technology, 1961. / Photocopy of typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 77-78).
74

Galaxy dissection : the evolution of the Disk of Messier 31 from stellar populations analysis /

Williams, Benjamin F. January 2002 (has links)
Thesis (Ph. D.)--University of Washington, 2002. / Vita. Includes bibliographical references (p. 211-220).
75

Evolution in the space density of clusters of galaxies in the Palomar Distant Cluster Survey /

Holden, Bradford. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics. / Includes bibliographical references. Also available on the Internet.
76

Galaxy spectral type and star formation as a function of density /

Carter, Barbara J. January 1999 (has links)
Thesis (Ph. D.)--University of Chicago, Dept. of Astronomy and Astrophysics. / Includes bibliographical references. Also available on the Internet.
77

The structure of the Coma cluster of galaxies

Noonan, Thomas Wyatt. January 1961 (has links)
Thesis (Ph. D.)--California Institute of Technology, 1961. / Photocopy of typescript. Includes bibliographical references (leaves 77-78).
78

Examination of Abell Clusters of Galaxies in Local Supercluster Environments

Krughoff, Karl Simon January 2004 (has links) (PDF)
No description available.
79

Variation of stellar populations and dark matter with time and environment

Shetty, Shravan January 2017 (has links)
In this thesis, I probe the stellar and dark matter component of galaxies in order to infer their evolutionary histories. I am doing this by studying two distinct galaxy population samples: (i) a high redshift sample at z&Tilde;1, and (ii) a high density environment sample of galaxies in the nearby Coma cluster. By comparing these samples to a sample of galaxies in the local Universe in a low density environment, I infer variation in their properties as a function of time and environment. For both samples, I create accurate dynamical models to infer the stellar Mass-to-Light ratios of the galaxies and their dark matter fractions. Furthermore, I model the stellar population of the galaxies using a full-spectrum technique while reproducing their star formation history in a non-parametric manner. In addition, I use IFS data for a subset of galaxies in the high density sample to create detailed dynamical models that strengthen the results found in that sample. Based on the quantities derived from these analyses, I present results on the IMF normalisation and dark matter fraction of galaxies in both samples. Furthermore, I studied the scaling relations of these galaxies and compared them to that observed for the ATLAS<sup>3D</sup> sample, which serves as a low density sample of the Local Universe, to infer variation in galaxy properties as a function of time and environment.
80

The faint end of the luminosity function in clusters of galaxies

De Propris, Roberto 13 July 2018 (has links)
We have determined luminosity functions, surface density distributions and color distributions for galaxies in eight clusters of galaxies at moderate redshift (z ~ 0.02) observed at the CFHT. 1) In the inner 2' of four cD clusters (Abell 2052, 2107, 2199 and 2666) we find very steep LFs, with α ~ -2.2 ± 0.2, where [special characters omitted](L) α Lα, where L is luminosity 2) For Abell 262, we find no significant contribution from cluster dwarfs in the field around NGC708 (the central cluster elliptical), although there is a small excess over background counts in the inner 3' of this field. For galaxies near UGC1308, we derive a LF with α ~ -1.4 ± 0.1. Galaxies in this field are concentrated towards UGC1308, so that the LF may be due to a population of satellites. 3) For the field centred on NGC1275 in Abell 426 we find a very steep LF, with α ~ -1.9 ± 0.1. We find that galaxies are not centrally concentrated towards NGC1275, except for a central ‘spike’ in their surface density distribution. We see a weak sequence of galaxies in the V vs V - I plot. There is a small color gradient in the sense of bluer galaxies near NGC1275. 4) For the field centred on NGC1265, we find again a very steep LF. Galaxies in this field tend to avoid the neighbourhood of NGC1265 and there is a mild red color gradient towards NGC1265. The LF within 100 kpc of NGC1265 is somewhat flatter than outside of this region, although the significance of this result is marginal. 5) For the field centred on UGC3274 in A539 we find a LF with α ~ -1.4 ± 0.1. We see that the galaxy distribution as a function of distance from UGC3274 is flat, except for a central spike. The LF appears to steepen towards UGC3274. There is a tight sequence of cluster galaxies in the V vs. V - I plot. There also appears to be a blueing trend towards UGC3274. 6) For Hercules (A2151) we derive a LF with α ~ -1.5 and M* = 12.2, where M* is a characteristic luminosity here converted to magnitudes. We interpret these results as supporting the conclusions by Biviano et al. (1995b) in Coma, namely that a population of dwarf galaxies with a steep LF constitutes the main body of the cluster, into which brighter giants fall later, thereby flattening the LF. We also find evidence that steep LFs are correlated with high gas densities. The blueing trend towards NGC1275 and UGC3274 is also consistent with recent star formation in dwarfs due to accretion of intracluster gas. / Graduate

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