1、The Age-metallicity Relation of Stars in Different Stellar Populations;
2、Three generations of stars may exist based on metallicity.
3、Different theories predict how this metallicity gradient changes over billions of years.
4、One clue comes from the metallicity of the disc's constituent stars.
5、In this thesis, we study the relation between the critical accretion rate and the metallicity via AGB stars approach.
6、Because we see the galaxy when it was young, this result suggests spiral discs start off with steep metallicity gradients.
7、Benson says that the steep metallicity gradient agrees with the long-standing but unconfirmed idea that spiral galaxies form their discs of stars from the inside out.
8、Because stars congregate at a galaxy's centre, the metallicity in most nearby spirals is greatest there and drops toward the edge.
9、In this model, a mass of gas collapses and creates lots of stars at the disc's centre, where the stars quickly boost the metallicity.
10、The absolute magnitudes in I and K bands of 58 red clump giants are computed and the relation between them and the metallicity are also showed.
11、If astronomers could observe metallicity gradients in spiral galaxies billions of light-years away, we could see how steep the gradients were billions of years ago and thus how they change over time.
12、A historic progress on recent studies of whether there is a possible age-metallicity relation of stars in the Galactic disk, especially in the Galactic thick disk, is reviewed in some details.
