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arXiv · 2504.11156

A preliminary cosmological analysis of stellar population synthesis of galaxies released by LAMOST LRS DR11

Yanhui Chen
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Abstract

The evolution of the universe together with the galaxies is one of the fundamental issues that we humans are most interested in. Both the observations of tidal streams from SDSS and the theory of $\Lambda$CDM support the hierarchical merging theory. The study of high redshift celestial bodies contributes to a more in-depth study of cosmology. The LAMOST low resolution search catalog DR11 v1.0 has released 11,939,296 spectra, including 11,581,542 stars, 275,302 galaxies, and 82,452 quasars, and so on. The data of 28,780 stellar population synthesis of galaxies and some high redshift quasars are used to do a preliminary statistical research. We selected the data with small errors for analysis and obtained some basic statistical conclusions. Older galaxies have relatively larger stellar velocity dispersions. The larger the metallicity, the greater the stellar velocity dispersion. These statistical results are reasonable and consistent with previous work. Because the stellar velocity dispersion is driven by the total mass of a galaxy at the first order and more massive galaxies have older ages and greater metallicities. The spectra of high redshift quasars show clear Gunn-Peterson trough and Lyman-$\alpha$ forest. The identified emission lines and high redshift celestial spectra released by LAMOST can be used for cosmological research.

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Yanhui Chen. 2025-04-15. A preliminary cosmological analysis of stellar population synthesis of galaxies released by LAMOST LRS DR11. https://arxiv.org/abs/2504.11156

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