Bibcode
Pérez, I.; Sánchez-Blázquez, P.
Bibliographical reference
HUNTING FOR THE DARK: THE HIDDEN SIDE OF GALAXY FORMATION. Edited by Victor P. Debattista and Cristina C. Popescu AIP Conference Proceedings, Volume 1240, pp. 253-254 (2010).
Advertised on:
6
2010
Citations
0
Refereed citations
0
Description
We have carried out a long term project to analyse the role played by
bars in bulge formation and the formation and evolution of bars from the
point of view of their star formation histories and stellar population.
To this aim, we have obtained high S/N long-slit spectra of 20 barred
galaxies, ranging in morphological types between S0 and Sb galaxies. We
have derived Lick/IDS indices along the bar for all the sample galaxies.
We find three types of bars according to their metallicity gradient;
bars with negative metallicity gradient, bars with null metallicity
gradient and galaxies with positive metallicity gradient. Regarding the
bulge region we find that the ages and metallicities are younger and
more metal rich, at a given σ, than the bulges of unbarred
galaxies. The E/Fe derived for the bulges of barred galaxies lie above
the values of the unbarred galaxies at a given σ. The gradients of
the metal indices in the bulge region tend to be negative, less metal
rich towards the end of the bulge. The gradient values show a large
scatter for galaxies with σ below 150 kms-1. The Balmer
indices show the opposite trend with the scatter of the gradients also
increasing for galaxies with σ below 150 kms-1. The
bulges of the barred galaxies in our sample have suffered a different
chemical enrichment history compared to unbarred galaxies of the same
morphological types, same σ distribution and same inclinations.