Evolutionary synthesis models for galaxy transformation in clusters

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Chemical evolution of spiral galaxies from redshift 4 to the present

Copyright International Astronomical Union/ Kluwe

Dust in Spectral Galaxy Evolution Models

Original paper can be found at: http://www.astrosociety.org/pubs/cs/195-221.html--Copyright Astronomical Society of the PacificTo analyse the effects of dust on the UV emission in various galaxy types we present our evolutionary synthesis models which includes dust absorption in a chemically consistent way. We show how the time evolution of the extinction is based on the evolution of both the gas content and the metallicity. We analyse the differences among various spectral types depending on the characteristic timescales of star formation and show the influence of the IMF. Our model SEDs are in very good agreement with templates from Kennicutt's and Kinney et al.'s atlases. With this comparision we point out the importance to aperture effects. Combined with a cosmological model we are able to predict the UV fluxes for different galaxy types from nearby to very high redshifts

Chemically Consistent Evolutionary Models With Dust

“The original publication is available at www.springerlink.com” Copyright Springer.Peer reviewe

On the Nature and Redshift Evolution of DLA Galaxies

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Tidal dwarf candidates in a sample of interacting galaxies

We present deep optical B,V,R images of a sample of 10 interacting systems which were selected for their resemblance to disturbed galaxies at high redshift. Photometry is performed on knots in the tidal features of the galaxies.We calculate a grid of evolutionary synthesis models with two metallicities and various burst strengths for systems consisting of some fraction of the stellar population of a progenitor spiral plus starburst. By comparison with two-color diagrams we interpret the photometric data, select from a total of about 100 condensations 36 star-forming objects that are located in the tidal features and predict their further evolution. Being more luminous by 4 mag than normal Hii regions we argue that these objects could be tidal dwarf galaxies or their progenitors, although they differ in number and mean luminosity from the already known tidal dwarf galaxies typically located at the end of tidal tails in nearby giant interacting systems. From comparison with our models we note that all objects show young burst ages. The young stellar component formed in these tidal dwarf candidates contributes up to 18% to the total stellar mass at the end of the starburst and dominates the optical luminosity. This may result in fading by up to 2.5 mag in B during the next 200 Myrs after the burst.Peer reviewe