相关论文: The Missing Metal Problem in Galaxy Clusters: Char…

Chemical abundances in the X-ray halos (also known as the intracluster medium, ICM) of clusters and groups of galaxies can be measured via prominent emission line features in their X-ray spectra. Elemental abundances are footprints of…

Metal-poor stars are key for studying the formation and evolution of the Galaxy. Evidence of the early mergers that built up the Galaxy remains in the distributions of abundances, kinematics, and orbital parameters of its stars. Several…

We study the chemical evolution and formation of the Galactic halo through the analysis of its stellar metallicity distribution function and some key elemental abundance patterns. Starting from the two-infall model for the Galaxy, which…

An early history of metal enrichment in the Galactic halo is studied. We investigate chemical inhomogeneity by using a stochastic chemical evolution model. The model confronts with metallicity distribution function of long-lived halo stars…

We investigate the radial metallicity gradients and azimuthal metallicity distributions on the Galactocentric $X$--$Y$ plane using mono-temperature stellar populations selected from LAMOST MRS young stellar sample. The estimated radial…

We present the result of near-infrared spectroscopy using Keck/MOSFIRE for 23 member galaxies in an X-ray cluster XCS2215 ($z=1.46$) to investigate the environmental dependence of gaseous flows and metallicities. We find that the…

We determined the metallicity ([Fe/H]), together with O, Na, Mg, Al, Si, Ca, Ti, Cr and Ni abundances for a sample of 10 unevolved or slightly evolved stars belonging to the open cluster M 67. We find an average metallicity [Fe/H]=0.03 +/-…

We measure a relation between the depth of four prominent rest-UV absorption complexes and metallicity for local galaxies and verify it up to z~3. We then apply this relation to a sample of 224 galaxies at 3.5 < z < 6.0 (<z> = 4.8) in…

Motivated by the recent detection of metals in different components of the high redshift universe and by the abundance ratios measured in the extremely metal-poor stars of our Galaxy, we study the nucleosynthesis constraints that this…

The combination of gas-phase oxygen abundances and stellar metallicities can provide us with unique insights into the metal enrichment histories of galaxies. In this work, we compare the stellar and gas-phase metallicities measured within a…

Clusters of galaxies allow a direct estimate of the metallicity and metal production yield on the largest scale so far. The ratio of the total iron mass in the ICM to the total optical luminosity of the cluster (the iron…

We present a comprehensive abundance analysis of 20 elements for 16 new low-metallicity stars from the Chemical Abundances of Stars in the Halo (CASH) project. The abundances have been derived from both Hobby-Eberly Telescope High…

We study the metallicity distribution and kinematic properties of 4,680 A/F/G/K-type giant stars with $|z|>$ 5 kpc selected from the LAMOST spectroscopic survey. The metallicity distribution of giant stars with 5 $<|z|\leqslant$ 15 kpc can…

A possible relation between the high dispersion in metallicity of metal-poor halo stars and the minor merger processes in the history of the Galaxy is presented. The foreign populations of stars in the satellites through minor merger…

Most of the metals (elements heavier than helium) ever produced by stars in the member galaxies of galaxy clusters currently reside within the hot, X-ray emitting intra-cluster gas. Observations of X-ray line emission from this…

We present a study of internal stellar population gradients in early-type cluster galaxies. Using the VLT VIMOS integral field unit, we observed 19 galaxies in the core of the Shapley Supercluster (z = 0.048). The radial trends in nine…

We present an unbiased method for evaluating the ranges of ages and metallicities which are allowed by the photometric properties of the stellar populations that dominate the light of early-type galaxies in clusters. The method is based on…

The Hubble Space Telescope has been used to obtain WFPC2 (V,I) photometry for a sample of 10,000 red giant stars in the outer halo of the giant elliptical NGC 5128. Comparison with the fiducial RGBs of Milky Way globular clusters and model…

We present radial velocities and chemical abundances for nine stars in the old, distant open clusters Be 18, Be 21, Be 22, Be 32, and PWM 4. For Be 18 and PWM 4, these are the first chemical abundance measurements. Combining our data with…

Based on the Beijing-Arizona-Taiwan-Connecticut (BATC) and Sloan Digital Sky Survey (SDSS) photometric data, we adopt SEDs fitting Method to evaluate the metallicity distribution for \sim40,000 main-sequence stars in the Galaxy. According…