相关论文: Dating Secular Evolution: Bar Ages from Stellar Ki…
Age dating starbursts is an exercise with many caveats. We attempt to summarise a discussion session that was lead along a rather optimistic guideline: the aim was to highlight that current age estimates, despite undeniable uncertainties,…
Masking the horizontal branch and giant stars allows unambiguous measurements of mean age and metallicity in simple old stellar populations from metal and hydrogen line strengths. Billion year resolution is possible in the luminous halos of…
Solar seismology has allowed precision measurements of both the static and dynamic structure of our local star, the Sun. In the near future, seismology of solar-like stars of different ages and masses, necessarily restricted by angular…
We obtained stellar ages and metallicities via spectrum fitting for a sample of 575 bulges with spectra available from the Sloan Digital Sky Survey. The structural properties of the galaxies have been studied in detail in Gadotti (2009b)…
We present a review of the present state of knowledge regarding the relative ages of Galactic globular clusters. First, we discuss the relevant galaxy formation models and describe the detailed predictions they make with respect to the…
During the last decade, the understanding of fine features of the structure and evolution of stars has become possible as a result of enormous progress made in the acquisition of high-quality observational and experimental data and of new…
We present the first results of a pilot study aimed at understanding the influence of bars on the evolution of galaxy discs through the study of their stellar content. We examine here the kinematics, star formation history, mass-weighted,…
Asteroseismology provides powerful means to probe stellar interiors. The oscillations frequencies are closely related to stellar interior properties via the density and sound speed profiles. Since these are tightly linked with the mass and…
We present new spectroscopic data for 21 barred spiral galaxies, which we use to explore the effect of bars on disk star formation, and to place constraints on the characteristic lifetimes of bar episodes. The analysis centres on regions of…
Results from the modelling of bars in nearly 300 galaxies are used to test predictions from theoretical work on the evolution of bars. Correlations are found between bar ellipticity and boxiness, between bar strength and normalised size,…
This review covers age-dating methods applied to young stellar populations in starburst galaxies with ages of 10^8 yr and less. First, recent advances in stellar modeling, both for the interior and the atmospheres, are discussed and…
Bars play a major role in driving the evolution of disk galaxies and in shaping their present properties. They cause angular momentum to be redistributed within the galaxy, emitted mainly from (near-)resonant material at the inner Lindblad…
During this last decade our knowledge of the evolutionary properties of stars has significantly improved. This result has been achieved thanks to our improved understanding of the physical behavior of stellar matter in the thermal regimes…
The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities…
Bars are common galactic structures in the local universe that play an important role in the secular evolution of galaxies, including the Milky Way. In particular, the velocity distribution of individual stars in our galaxy is useful to…
One third of present-day spirals host optically visible strong bars that drive their dynamical evolution. However, the fundamental question of how bars evolve over cosmological times has yet to be addressed, and even the frequency of bars…
I review some of the work on bars which is closely linked to the bar/bulge system in our Galaxy. Several independent studies, using totally independent methods, come to the same results about the 3D structure of a bar, i.e., that a bar is…
We consider models of gas flow in spiral galaxies in which the spiral structure has been excited by various possible mechanisms: a global steady density wave, self-gravity of the stellar disc and an external tidal interaction, as well as…
We show observations obtained with the integral field spectrometer OASIS for the central regions of a sample of barred galaxies. The high spatial resolution of the instrument allows to distinguish various structures within these regions as…
Disk galaxies evolve over time through processes that may rearrange both the radial mass profile and the metallicity distribution within the disk. This review of such slow changes is largely, though not entirely, restricted to…