Related papers: Metallicities of Classical Cepheids in the Inner G…
The radial gradient of gas-phase metallicity is a powerful probe of the chemical and structural evolution of star-forming galaxies, closely tied to disk formation and gas kinematics in the early universe. We present spatially resolved…
Classical Cepheids are the most popular distance indicators and tracers of young stellar populations. The key advantage is that they are bright and they can be easily identified in Local Group and Local Volume galaxies. Their evolutionary…
Galaxies at low-redshift typically possess negative gas-phase metallicity gradients (centres more metal-rich than their outskirts). Whereas, it is not uncommon to observe positive metallicity gradients in higher-redshift galaxies ($z…
Radial metallicity gradients are observed in the disks of the Milky Way and in several other spiral galaxies. In the case of the Milky Way, many objects can be used to determine the gradients, such as HII regions, B stars, Cepheids, open…
We report the first sub-kiloparsec spatial resolution measurements of strongly inverted gas-phase metallicity gradients in two dwarf galaxies at $z$$\sim$2. The galaxies have stellar masses $\sim$$10^9M_\odot$, specific star-formation rate…
We present a differential study of 500 Magellanic Cepheids with 3 million measurements obtained as a by-product of the EROS microlensing survey. The data-set is unbiased and provides an excellent basis for a differential analysis between…
Based on SDSS DR8, we have selected a sample of 1728 red horizontal branch stars with |Z|<3 kpc by using a color-metallicity relation and stellar parameters. The sample stars clearly trace a typical thick disk population with peaks at…
Using a sample of over 70, 000 red clump (RC) stars with $5$-$10$% distance accuracy selected from the LAMOST Spectroscopic Survey of the Galactic Anti-center (LSS-GAC), we study the radial and vertical gradients of the Galactic disk(s)…
The stellar metallicity gradients of disc galaxies provide information on the disc assembly, star formation processes and chemical evolution. They also might store information on dynamical processes which could affect the distribution of…
A catalog of Cepheid variables is used to probe the kinematics of the Galactic disk. Radial velocities are measured for eight distant Cepheids toward l = 300; these new Cepheids provide a particularly good constraint on the distance to the…
We point out that the absolute magnitude of the Galactic Cepheids, which have been used for local calibrations for Cepheid period-luminosity relation, shows an unexpectedly large metal abundance effect. This indicates that either Cepheids…
Stellar metallicity gradients in the outer regions of galaxies are a critical tool for disentangling the contributions of in-situ and ex-situ formed stars. In the two-phase galaxy formation scenario, the initial gas collapse creates steep…
We revisit the problem of the positive correlation between age and Galactocentric distance seen in Galactic Classical Cepheids, which at first sight may seem counter-intuitive in the context of inside-out galaxy formation. To explain it, we…
Although there have been numerous studies of chemical abundances in the Galactic bulge, the central two degrees have been relatively unexplored due to the heavy and variable interstellar extinction, extreme stellar crowding, and the…
This paper explores the gas metallicity gradients in a sample of 25 nearby galaxies using new Integral Field Spectroscopy observations from the Metal-THINGS survey. We derive and study the resolved diffuse ionised gas content, Baldwin,…
We present Galactic mean metallicity maps derived from the first year of the SDSS-III APOGEE experiment. Mean abundances in different zones of Galactocentric radius (0 < R < 15 kpc) at a range of heights above the plane (0 < |z| < 3 kpc),…
We present results of a survey of a 6-square-degree region near l=60, b=0 to search for distant Milky Way Cepheids. Few MW Cepheids are known at distances >~ R_0, limiting large-scale MW disk models derived from Cepheid kinematics; this…
We gathered more than 1130 high-resolution optical spectra for more than 250 Galactic classical Cepheids. The spectra were collected with different optical spectrographs: UVES at VLT, HARPS at 3.6m, FEROS at 2.2m MPG/ESO, and STELLA. To…
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…
We present the results from a multi-epoch survey of two regions of M33 using the 3.5m WIYN telescope. The inner field is located close to the centre of the galaxy, with the outer region situated about 5.1 kpc away in the southern spiral…