Galactic bulges: the importance of early formation scenarios vs. secular evolution. Issue Volume 10:Issue S309(2014) (9th February 2015)

• Record Type: Journal Article
• Authors: Seidel, Marja K.; Cacho, R.; Ruiz-Lara, T.; Falcón-Barroso, J.; Pérez, I.; Sánchez-Blázquez, P.; Vogt, F. P. A.; Ness, M.; Freeman, K.; Aniyan, S.
• Editors: Ziegler, Bodo L.; Combes, Françoise; Dannerbauer, Helmut; Verdugo, Miguel
• Is Part Of: Proceedings of the International Astronomical Union. Volume 10:Issue S309(2014)
• Page Start: 163
• Page End: 164
• Publication Date: 2015-02-09
• Subjects: galaxies: individual (NGC 5701, NGC 6753, NGC 7552), -- galaxies: bulges, -- galaxies: evolution, -- galaxies: kinematics and dynamics, -- galaxies: stellar content, -- techniques: spectroscopic; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921314009569
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: We study the stellar content of three galactic bulges with the high resolution gratings (R=7000) of the WiFeS integral field unit in order to better understand their formation and evolution. In all cases we find that at least 50% of the stellar mass already existed 12 Gyrs ago, more than currently predicted by simulations. A younger component (age between ∼1 to ∼8 Gyrs) is also prominent and its present day distribution seems to be much more affected by morphological structures, especially bars, than the older one. This in-depth analysis supports the notion of increasing complexity in bulges which cannot be achieved by mergers alone, but requires a non-negligible contribution from secular evolution.