Related papers: Metals in M33
We report on the discovery of seven low-metallicity stars selected from the Hamburg/ESO Survey, six of which are extremely metal-poor ([Fe/H]<-3.0), with four having [Fe/H]<-3.5. Chemical abundances or upper limits are derived for these…
We present magnesium abundances derived from high resolution spectra using several Mg I and two high excitation Mg II lines for 19 metal-poor stars with [Fe/H] values between -1.1 and +0.2. The main goal is to search for systematic…
The most metal-poor stars found in the Galaxy and in nearby galaxies are witnesses of the early evolution of the Universe. In a general picture in which we expect the metallicity to increase monotonically with time, as a result of the metal…
The determination of the stellar parameters of M dwarfs is of prime importance in the fields of galactic, stellar and planetary astronomy. M stars are the least studied galactic component regarding their fundamental parameters. Yet, they…
Recent work suggests that galaxy evolution, and the build-up of stellar mass (M*) over cosmic time, is characterized by changes with redshift of star formation rate (SFR) and oxygen abundance (O/H). In a companion paper, we have compiled a…
The inner disc of the local group galaxy M33 appears to be in settled rotational balance, and near IR images reveal a mild, large-scale, two-arm spiral pattern with no strong bar. We have constructed N-body models that match all the…
We present spectroscopic abundances and radial velocities for giant stars in the Galactic globular cluster omega Centauri based on the CaII infrared triplet. Two samples of stars were observed: 234 stars at M_V = 1.25 on the lower giant…
Hot atmospheres of massive galaxies are enriched with metals. Elemental abundances measured in the X-ray band have been used to study the chemical enrichment of supernova remnants, elliptical galaxies, groups and clusters of galaxies. Here…
Two aspects of the chemical evolution of 4He in the Galaxy are considered on the basis of a sample of disk planetary nebulae by the application of corrections due to the contamination of 4He from the progenitor stars. First, the He/H radial…
We analyze the metal accumulation in dwarf and spiral galaxies by following the history of metal enrichment and outflows in a suite of twenty high-resolution simulated galaxies. These simulations agree with the observed stellar and…
The early stages of a galaxy's evolution leave an imprint on its metallicity distribution. We discuss the origins and evolution of radial metallicity gradients in discs of spiral galaxies using an analytical chemical evolution model. We…
The metallicity distribution function (MDF) of the Galactic bulge features a multi-peak shape, with a metal-poor peak at [Fe/H]=-0.3 dex and a metal-rich peak at [Fe/H]=+0.3 dex. This bimodality is also seen in [alpha/Fe] versus [Fe/H]…
Metallicity is one of the crucial factors that determine stellar evolution. To characterize the properties of stellar populations one needs to know the fraction of stars forming at different metallicities. Knowing how this fraction evolves…
Observations of evolution in the dust-to-metal ratio allow us to constrain the dominant dust processing mechanisms. In this work, we present a study of the dust-to-metal and dust-to-gas ratios in a sub-sample of ~500 DustPedia galaxies.…
Using Gemini QuickStart infrared observations of the central 22" of M33, we analyze the stellar populations in this controversial region. Based on the slope of the giant branch we estimate the mean metallicity to be -0.26+/-0.27, and from…
We present chemical abundances in K and M red-giant members of the Galactic bulge derived from high-resolution infrared spectra obtained with the Phoenix spectrograph on Gemini-South. The elements studied are carbon, nitrogen, oxygen,…
We present a metallicity analysis of 83 late-type giants within the central 1 pc of the Milky Way. K-band spectroscopy of these stars were obtained with the medium-spectral resolution integral-field spectrograph NIFS on Gemini North using…
We report on the metal distribution in the intracluster medium around the radio galaxy 4C+55.16 (z=0.24) observed with the Chandra X-ray Observatory. The radial metallicity profile shows a dramatic change at 10 arcsec (~50 kpc) in radius…
We present detailed chemical abundances for $>$20 elements in $\sim$30 globular clusters in M31. These results have been obtained using high resolution ($\lambda/\Delta\lambda\sim$24,000) spectra of their integrated light and analyzed using…
M 2 has been claimed to posses three distinct stellar components that are enhanced in iron relative to each other. We use equivalent width measurements from 14 red giant branch stars from which Yong et al. detect a $\sim$0.8 dex wide,…