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Showing 1 to 11 of 11 for “"Stellar Ages"”.
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Open clusters and HII regions of our Galaxy
… are essential laboratories for understanding stellar evolution, as they allow constraints to be placed on stellar ages and luminosities. As distance indicators they are also important tracers of star formation in the Milky Way. One such cluster is Trumpler 27 that we identified for detailed …
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Prospecting for elements: Galactic halo planetary nebulae abundances and Virgo spiral galaxy color profiles.
… as a first step to probing the underlying stellar metallicity. Decomposition techniques have been used to produce estimates of spiral bulge/disk masses and luminosities in all three J, H, & K bands, as well as to explore the variation of mass-to-light ratios within the separate galaxy …
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Regulating and Quenching Star Formation in Galaxies across the Cosmic Epochs
… the MaNGA survey, I report the discovery of a stellar Fundamental Metallicity Relation, a smooth relation between stellar mass, star-formation rate and stellar metallicity, analogous to the well-established gas-phase FMR. The existence of the stellar FMR suggests that the metal-poor gas …
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Chromospheric activity and lithium abundance in the NGC2516 and NGC3766 open clusters
… of late type stars in open clusters of different ages. The study of open cluster is very important for our understanding of stellar evolution and atmospheres, since all cluster members have almost the same age and chemical composition and this allows to infer their properties more easily than …
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Constraining Stellar Evolution in Young Open Clusters with NGTS
Understanding stellar evolution is fundamental to astronomy, yet there remain significant gaps in our knowledge. Scientific progress requires testing our best explanations against observation, and open clusters act as key test sites for theories of stellar evolution. Observations of young open …
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Investigating the Relationship Between Chemical Abundance Ratios and Ages in Red Giant Stars
… parameter in that mission, the measurement of stellar ages for red giant stars, has been a challenge. Red giants are important to study because they span a large range of ages, and, due to their intrinsic brightness, allow us to probe further in the Galaxy. Recent developments have enabled the …
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Investigating the Relationship Between Chemical Abundance Ratios and Ages in Red Giant Stars
… parameter in that mission, the measurement of stellar ages for red giant stars, has been a challenge. Red giants are important to study because they span a large range of ages, and, due to their intrinsic brightness, allow us to probe further in the Galaxy. Recent developments have enabled the …
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Rotation Period Distributions and Light Curve Morphologies of Low Mass Stars and Young Associations
… the rotation period distributions of a range of stellar types and ages. Traditionally, M dwarf stars and young stars were challenging to describe due to their intrinsic faintness and dispersed sky positions respectively. I approached this subject from several directions.</p>
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Unveiling the History and Nature of the Milky Way with Galactic Surveys and Numerical Simulations
… structure as a function of [Fe/H], [α/Fe] and stellar ages (based on the surface abundances of Carbon and Nitrogen), as measured by the APOGEE survey. I measure the disc density profile, fitting the scale heights and lengths of mono-age, mono-[Fe/H] sub-populations in the high and low [α/Fe] …
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Connecting simulations and observations in galaxy formation studies
… show that for some quantities such as the stellar ages, metallicities and gas oxygen abundances large differences can appear, depending on the technique applied in the derivation. In a second work we compare a set of fifteen galaxies similar in mass to the Milky Way and with a quiet merger …
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Chemical and kinematical evolution in nearby dwarf spheroidal galaxies
… properties, such as the omnipresence of old stellar populations, their gas deficiency, their high velocity dispersion and at dispersion profiles provide stringent tests of the paradigm of galaxy formation and render these systems important benchmarks for studying galactic evolution from the …