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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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