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OATS-DAUT SEMINAR
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Speaker: Simone Recchi (INAF/Oss. Astr. Trieste)

Title: Early evolution of Tidal Dwarf Galaxies

Date: Wednesday, November 22nd, 2006
Time: 12:00 noon
Venue: Villa Bazzoni

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Abstract:
I will present a progress report of a project concerning the dynamical and chemical evolution of Tidal Dwarf Galaxies. Tidal tails, resulting from the interactions of large galaxies, can create self-gravitating structures which are the seeds of dwarf galaxies. In these galaxies, commonly known as Tidal Dwarf Galaxies , the Dark Matter content is very small, which make them more vulnerable to stellar feedback. Our first step is therefore to understand whether a model galaxy without Dark Matter can sustain the feedback of the ongoing star formation. We present tests of the evolution of models in which star formation efficiency, temperature threshold, initial distribution of gas and infall are varied. We conclude that it is feasible to keep a fraction of gas bound for several hundreds of Myr and that the development of galactic winds does not necessarily stop continuous star formation. At the end of my presentation I will briefly introduce a project concerning the self-enrichment of Globular Clusters. I shall summarize the chemical properties of Globular Clusters, focusing on the hints that some of the stars of the Globular Clusters are polluted by the ejecta released by older stars, probably of intermediate-mass, demonstrating therefore that Globular Clusters are not coeval objects. I will show the strategies and the first results adopted to sharpen our understanding on these issues.
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