35 resultados para Threshing.


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Mode of access: Internet.

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We present BVI photometry of 190 galaxies in the central 4 x 3 deg(2) region of the Fornax cluster observed with the Michigan Curtis Schmidt Telescope. Results from the Fornax Cluster Spectroscopic Survey (FCSS) and the Flair-II Fornax Surveys have been used to confirm the membership status of galaxies in the Fornax Cluster Catalogue (FCC). In our catalogue of 213 member galaxies, 92 (43 per cent) have confirmed radial velocities. In this paper, we investigate the surface brightness-magnitude relation for Fornax cluster galaxies. Particular attention is given to the sample of cluster dwarfs and the newly discovered ultracompact dwarf galaxies (UCDs) from the FCSS. We examine the reliability of the surface brightness-magnitude relation as a method for determining cluster membership and find that at surface brightnesses fainter than 22 mag arcsec(-2), it fails in its ability to distinguish between cluster members and barely resolved background galaxies. Cluster members exhibit a strong surface brightness-magnitude relation. Both elliptical (E) galaxies and dwarf elliptical (dE) galaxies increase in surface brightness as luminosity decreases. The UCDs lie off the locus of the relation. B-V and V-I colours are determined for a sample of 113 cluster galaxies and the colour-magnitude relation is explored for each morphological type. The UCDs lie off the locus of the colour-magnitude relation. Their mean V - I colours (similar to1.09) are similar to those of globular clusters associated with NGC 1399. The location of the UCDs on both surface brightness and colour-magnitude plots supports the 'galaxy threshing' model for infalling nucleated dwarf elliptical (dE, N) galaxies.

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We review the evidence that the ultra-compact dwarf (UCD) galaxies we recently discovered in the Fornax Cluster form a new, previously unknown class of galaxies and we discuss possible scenarios for their formation. We then present recent results that UCDs are also present in the Virgo Cluster, and that there is a much larger than expected population of fainter UCDs in the Fornax Cluster. The size and properties of this population may lead us to revise our original 'galaxy threshing' hypothesis for the formation of UCDs.

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We have discovered nine ultracompact dwarf galaxies (UCDs) in the Virgo Cluster, extending samples of these objects outside the Fornax Cluster. Using the Two Degree Field (2dF) multifiber spectrograph on the Anglo-Australian Telescope, the new Virgo members were found among 1500 color-selected, starlike targets with 16: 0 < b(j) < 20.2 in a 2 degrees diameter field centered on M87 (NGC 4486). The newly found UCDs are comparable to the UCDs in the Fornax Cluster, with sizes less than or similar to 100 pc, -12.9 < M-B < -10.7, and exhibiting red absorption-line spectra, indicative of an older stellar population. The properties of these objects remain consistent with the tidal threshing model for the origin of UCDs from the surviving nuclei of nucleated dwarf elliptical galaxies disrupted in the cluster core but can also be explained as objects that were formed by mergers of star clusters created in galaxy interactions. The discovery that UCDs exist in Virgo shows that this galaxy type is probably a ubiquitous phenomenon in clusters of galaxies; coupled with their possible origin by tidal threshing, the UCD population is a potential indicator and probe of the formation history of a given cluster. We also describe one additional bright UCD with M-B = -12.0 in the core of the Fornax Cluster. We find no further UCDs in our Fornax Cluster Spectroscopic Survey down to bj 19.5 in two additional 2dF fields extending as far as 3 degrees from the center of the cluster. All six Fornax bright UCDs identified with 2dF lie within 0.degrees 5 (projected distance of 170 kpc) of the central elliptical galaxy NGC 1399.

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This work consists of a discussion, analysis and reading of Borges’stories, in that the problem of interest pronounces to the language, to the speech and the deed, sending them so much to the Literature with relationship to the Philosophy, so much to the statute of the ficcional, with relationship to the of the ontologic. In that optics, it intends to show the Borges deed as warp of the death, of the allegorical and of the metaphorical, in the sense of bringing for the ficcional lines different from the Real, elaborating the speech for besides the statement, reaching the interstic, the silence, the interruptions and the suspension of the representation. In that discursive elaboration, a crossing is pointed in the letter, affected for unspeakable sensations, crossing the processes of memory, imaginary and real, in which the time counting makes to emerge the difference and the repetition. In these if constituting territorial negotioting that they lead the characters to imaginary spaces as possibilities of the real, allowing them executes mobility for desterritory it self and reterritory itself, according to the change forces that show in your threshing. For so much, it is placed as mark a bibliographical research orientated by authors as Maurice Blanchot (2008), Kátia Muricy (1998), João Adolfo Hansen (2006), Susan Sontag (2007), Mário Bruno (2004), Juan Manuel García Ramos (2003), Elizabeth Kübler Ross (2008), Walter Benjamin (1984), Gilles Deleuze (1997; 2006; 2009), Gilles Deleuze and Félix Guattari (1995; 1996; 1997). The theoretical corpus and of discussion, it is constituted to leave of those authors, assisting to the implicit qualitative character in the construction of this thesis. What about to the literary corpus, this is composed by the stories The writing of the God, The two kings and the two labyrinths, The lottery of Babylon, The metaphor, The library of Babel, The mirror and the mask, A theologian in death and The dead man.