TY - JOUR
T1 - Galactic bulges
T2 - The importance of early formation scenarios vs. secular evolution
AU - Seidel, Marja K.
AU - Cacho, R.
AU - Ruiz-Lara, T.
AU - Falcón-Barroso, J.
AU - Pérez, I.
AU - Sánchez-Blázquez, P.
AU - Vogt, F. P.A.
AU - Ness, M.
AU - Freeman, K.
AU - Aniyan, S.
N1 - Publisher Copyright:
© International Astronomical Union 2015.
PY - 2014
Y1 - 2014
N2 - 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.
AB - 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.
KW - Galaxies: bulges
KW - Galaxies: evolution
KW - Galaxies: individual (NGC 5701, NGC 6753, NGC 7552)
KW - Galaxies: kinematics and dynamics
KW - Galaxies: stellar content
KW - Techniques: spectroscopic
UR - http://www.scopus.com/inward/record.url?scp=84922532321&partnerID=8YFLogxK
U2 - 10.1017/S1743921314009569
DO - 10.1017/S1743921314009569
M3 - Article
SN - 1743-9213
VL - 10
SP - 163
EP - 164
JO - Proceedings of the International Astronomical Union
JF - Proceedings of the International Astronomical Union
ER -