Related papers: Models for Pop I stars: implications for age deter…
The observable characteristics and subsequent evolution of young stellar populations is dominated by their massive stars. As our understanding of those massive stars and the factors affecting their evolution improves, so our interpretation…
The rotation rate of a star has important implications for the detectability, characterisation and stability of any planets that may be orbiting it. This chapter gives a brief overview of stellar rotation before describing the methods used…
Galactic archaeology relies on accurate stellar parameters to reconstruct the galaxy's history, including information on stellar ages. While the precision of data has improved significantly in recent years, stellar models used for age…
Stellar evolution models are a cornerstone of young star astrophysics, which necessitates that they yield accurate and reliable predictions of stellar properties. Here, I review the current performance of stellar evolution models against…
The first generation of stars, often called Population III (or Pop III), form from metal-free primordial gas at redshifts 30 and below. They dominate the cosmic star formation history until redshifts 15 to 20, at which point the formation…
Ages are key to truly understand a large plethora of astrophysical phenomena. On the other hand, stellar clusters are open windows to understand stellar evolution, specifically, the change with time and mass of different stellar properties.…
Detailed modelling of stellar oscillations is able to give precise estimates for stellar ages, but the inferred results typically depend on the adopted model parameters used for the age inference. High-quality asteroseismic data with…
Pop III stars are the key to the character of primeval galaxies, the first heavy elements, the onset of cosmological reionization, and the seeds of supermassive black holes. Unfortunately, in spite of their increasing sophistication,…
Rotation has a number of important effects on the evolution of stars. Apart from structural changes because of the centrifugal force, turbulent mixing and meridional circulation caused by rotation can dramatically affect a star's chemical…
Age is one of the most fundamental parameters of stars, yet it is one of the hardest to determine as it requires modelling various aspects of stellar formation and evolution. When we compare the ages derived from isochronal and dynamical…
We discuss the cosmological significance of the transition from the Pop III to Pop II mode of star formation in the early universe, and when and how it may occur in primordial galaxies. Observations that could detect this transition include…
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…
It has become a common practice within the exoplanet field to say that "to know the star is to know the planet." The properties of the host star have a strong, direct influence on the interior and surface conditions of the orbiting planet…
Stellar models provide a vital basis for many aspects of astronomy and astrophysics. Recent advances in observational astronomy -- through asteroseismology, precision photometry, high-resolution spectroscopy, and large-scale surveys -- are…
Stellar population synthesis models are an essential tool with which galaxy physical parameters are extracted from observations. However they are built on assumptions designed for use in the local Universe, and not always appropriate to…
Determining the properties of old stellar populations (those with age >1 Gyr) has long involved the comparison of their integrated light, either in the form of photometry or spectroscopic indexes, with empirical or synthetic templates. Here…
We present three new methods for determining the age of groups of pre-main-sequence stars. The first, creating empirical isochrones allows us to create a robust age ordering, but not to derive actual ages. The second, using the width of the…
Horizontal branch (HB) stars play a particularly important role in the "age debate," since they are at the very center of the long-standing "second parameter" problem. In this review, I discuss some recent progress in our understanding of…
The rotation-mass-age relationship offers a promising avenue for measuring the ages of field stars, assuming the attendant uncertainties to this technique can be well characterized. We model stellar angular momentum evolution starting with…
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,…