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Seismological measurement of stellar ages
Nature, 1987Accurate measurements of stellar acoustic oscillation frequencies, which are likely to be obtained in the coming years, will provide important new data enabling us to diagnose the internal structure of stars. The ages of main-sequence stars are likely to be determined to a higher precision than has been possible in the past and much more accurate ...
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Could Stellar Ash Revise Cosmic Ages?
Science, 1996The helium and other elements made by nuclear burning in red giant stars were thought to stay bottled up deep inside the stars, but observers have noticed that some of this ash leaks to the stellar surface. A new set of calculations now shows that the ash makes the giants brighter than expected, which in turn casts doubt on a whole set of assumptions ...
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Stellar Age and Mass Determination
2012We outline a Bayesian method to determine stellar ages and masses from observationally derived surface luminosities and effective temperatures. We then illustrate the procedure with two test stars.
{Mowlavi} N., {Eyer} L.
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Preparation of Ag Stellar Dendrites: Modeling the Growth of Stellar Snowflakes
Crystal Growth & Design, 2014The synthesis of Ag stellar dendrites was achieved using a solution-phase method by modeling the growth of stellar snowflakes. In the synthesis, 2,3-bis(2-pyridyl)pyrazine (dpp) acted as the growth-directing agent, forming hexagonal structures that served as the nuclei for the growth of stellar dendrites.
Choon Hwee Bernard Ng, Wai Yip Fan
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Stellar Rotation and Age Determination
EAS Publications Series, 2010In this preliminary analysis we discuss on a statistical inversion method applied to the measured stellar V rot sin i . Our goal is to obtain the V rot of the cluster stars which is a key parameter of stellar evolution computations.
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New Age Indicators for Stellar Populations
Chinese Physics Letters, 2000We apply the method of principal component analysis to a sample of simple stellar populations to select some age sensitive spectral indices. Besides the well-known age sensitive index Hβ, we also find some new age sensitive indices, G4300 and Fe4383, C24668, and Mgb.
Kong Xu, Cheng Fu-Zhen
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Stellar ages and their cosmological context
EAS Publications Series, 2014Stellar ages have traditionally been used to constrain cosmological models by setting lower limits to the age of the universe. We quickly review the basic cosmological concepts that underpin the derivation of a finite age, and the constraints given by the measure of cosmological parameters at a redshift z ∼ 1000.
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Stellar Age Inference with Rotation (+ Activity?)
Ages of low mass main sequence (MS) stars can be challenging to measure because of their long MS lifetimes. While gyrochronology (a method of dating such stars using rotation period) is somewhat effective, the observed dispersion in rotation rates for similar coeval stars has historically been difficult to model.Van-Lane, Phil +8 more
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Age-dating methods: a synthetic view "Different age estimation methods exist for individual stars, but no single method works well for stars of all evolutionary stages " (Dave Soderblom, ARAA, 2010).
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