Related papers: NGC 1866: a workbench for stellar evolution
Convective core overshoot affects stellar evolution rates and the dating of stellar populations. In this paper, we provide a patch to the $Y^2$ isochrones with an improved treatment of convective core overshoot. The new tracks cover the…
Connecting high-redshift galaxies to their low-redshift descendants is one of the most important and challenging tasks of galaxy evolution studies. In this work, we investigate whether incorporating high-redshift environmental factors…
Abundance trends in heavier elements with evolutionary phase have been shown to exist in the globular cluster NGC 6752 [Fe/H]=-1.6. These trends are a result of atomic diffusion and additional (non-convective) mixing. Studying such trends…
High spectral resolution evolutionary synthesis models have become a routinely used ingredient in extragalactic work, and as such deserve thorough testing. Star clusters are ideal laboratories for such tests. This paper applies the spectral…
We have developed a new simulation code aimed at studying the stellar dynamics of a galactic central star cluster surrounding a massive black hole. In order to include all the relevant physical ingredients (2-body relaxation, stellar mass…
Convective-core overshoot mixing is a significant uncertainty in stellar evolution. Because numerical simulations and turbulent convection models predict exponentially decreasing radial rms turbulent velocity, a popular treatment of the…
An optical spectrum of the Elson et al. (1998) candidate luminous white dwarf in the young LMC cluster NGC1818 shows conclusively that it is not a degenerate star. A model atmosphere fit gives T=31,500K and log g=4.4, typical of a…
Theories of stellar convective core overshoot can be examined through analysis of pulsating stars. Better accuracy can be achieved by obtaining external constraints such as those provided by observing pulsating stars in eclipsing binary…
The abundance of galaxy clusters in the low-redshift universe provides an important cosmological test, constraining a product of the initial amplitude of fluctuations and the amount by which they have grown since early times. The degeneracy…
The possibility to constrain cosmological parameters from galaxy surveys using field-level machine learning methods that bypass traditional summary statistics analyses, depends crucially on our ability to generate simulated training sets.…
Inferences from observations clearly show that mixing in stars extends beyond the convective boundaries defined by mixing length theory. This triggered the proposal of a variety of prescriptions to include additional mixing in stellar…
Context. The one-dimensional treatment of turbulent convection had large successes until the early 2000s. However, the recent abundance and precision of observational data shows that this problem is far from solved. A modern approach should…
Mixing in the convective core is quite uncertain in core helium burning stars. In order to explore the overshooting mixing beyond the convective core, we incorporated the $k$-$\omega$ proposed by Li (2012, 2017) into MESA, and investigated…
Over the last decades, several independent studies have shown the need for large convective boundary mixing (CBM) and convective core sizes in massive stars to reproduce a variety of their observed properties. Yet, stars more massive than…
We examine contributions of second order physical processes to results of stellar evolution calculations amenable to direct observational testing. In the first paper in the series (Young et al. 2001) we established baseline results using…
We present Hubble Space Telescope ACS deep photometry of the intermediate-age globular cluster NGC 1783 in the Large Magellanic Cloud. By using this photometric dataset, we have determined the degree of ellipticity of the cluster…
Uncertainties on central mixing in main sequence (MS) and core He-burning (He-B) phases affect key predictions of stellar evolution such as late evolutionary phases, chemical enrichment, ages etc. We propose a test of the extension of…
The diagnostic age versus mass-to-light ratio diagram is often used in attempts to constrain the shape of the stellar initial mass function (IMF), and the potential longevity of extragalactic young to intermediate-age massive star clusters.…
Recently, Li et al. (2016) claimed to have found evidence for multiple generations of stars in the intermediate age clusters NGC 1783, NGC 1696 and NGC 411 in the Large and Small Magellanic Clouds (LMC/SMC). Here we show that these young…
The Sun is the most studied of all stars. It is a reference for all other observed stars and a laboratory of fundamental physics helping us understand processes occuring in conditions irreproducible on Earth. However, our understanding of…