English
Related papers

Related papers: The G-dwarf problem in the Galaxy

200 papers

We combine spectroscopic metallicity values with integrated narrowband continuum colors to explore the internal metallicity distribution in early-type galaxies. The different techniques for determining metallicity (indices versus colors)…

Astrophysics · Physics 2008-10-23 J. Schombert , K. Rakos

We address the question of the occurrence of star formation bursts in the solar neighbourhood by using the metallicity distribution of the G dwarfs. We present a method to recover the star formation history using simultaneously the…

Astrophysics · Physics 2015-06-24 Helio J. Rocha-Pinto , Walter J. Maciel

The levels of heavy elements in stars are the product of enhancement by previous stellar generations, and the distribution of this metallicity among the population contains clues to the process by which a galaxy formed. Most famously, the…

Standard analytical chemical evolution modelling of galaxies has been assuming the stellar initial mass function (IMF) to be invariant and fully sampled allowing fractions of massive stars to contribute even in dwarf galaxies with very low…

Astrophysics of Galaxies · Physics 2015-06-23 S. Recchi , P. Kroupa

We study the detailed properties of the radial metallicity gradient in the stellar disk of our Galaxy to constrain its chemical and structural evolution. For this purpose we select and analyze $\sim$ 18,500 disk stars taken from two…

Astrophysics of Galaxies · Physics 2015-06-19 Daisuke Toyouchi , Masashi Chiba

We discuss the star formation history of the Galaxy, based on the observations of extremely metal-poor stars (EMP) in the Galactic halo, to gain an insight into the evolution and structure formation in the early universe. The initialmass…

Astrophysics · Physics 2008-11-26 Yutaka Komiya , Takuma Suda , Asao Habe , Masayuki Y. Fujimoto

In this work we have assumed a Hernquist model with an inside-out formation for the Galactic bulge and, using a chemical evolution model, we were able obtain the bulge metallicity distribution function (MDF) for different radial regions.…

Astrophysics of Galaxies · Physics 2017-12-06 O. Cavichia , M. Mollá

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]…

Astrophysics of Galaxies · Physics 2024-05-22 M. Molero , F. Matteucci , E. Spitoni , A. Rojas-Arriagada , R. M. Rich

I present a new Galactic chemical evolution model motivated by and grounded in the hierarchical theory of galaxy formation, as expressed by a halo merger history of the Galaxy. This model accurately reproduces the "metallicity distribution…

Astrophysics · Physics 2009-11-13 Jason Tumlinson

Stellar population models with abundance distributions determined from the analytic Simple model of chemical evolution fail to match observations of the nuclei of bulge-dominated galaxies in three respects. First, the spectral energy…

Astrophysics · Physics 2009-10-28 Guy Worthey , Ben Dorman , Lewis Jones

The entire evolution of the Milky Way, including its mass-assembly and star-formation history, is imprinted onto the chemo-dynamical distribution function of its member stars, f(x, v, [X/H]), in the multi-dimensional phase space spanned by…

Astrophysics of Galaxies · Physics 2015-06-18 Kohei Hattori , Yuzuru Yoshii , Timothy C. Beers , Daniela Carollo , Young Sun Lee

Large numbers of low-to-medium resolution spectra of M-type dwarf stars from both the local Galactic disk and halo are available from various surveys. In order to fully exploit these data, we develop a template-fit method using a set of…

Solar and Stellar Astrophysics · Physics 2020-03-11 Neda Hejazi , Sebastien Lepine , Derek Homeier , R. Michael Rich , Michael M. Shara

Based on Sloan Digital Sky Survey (SDSS) photometric data, Gu developed a new Monte-Carlo-based method for estimating the stellar metallicity distribution functions (MDFs). This method enables a more reliable determination of MDFs compared…

Astrophysics of Galaxies · Physics 2019-06-05 Jiayin Gu , Cuihua Du , Wenbo Zuo

Dwarf galaxies generally follow a mass-metallicity (MZ) relation, where more massive objects retain a larger fraction of heavy elements. Young tidal dwarf galaxies (TDGs), born in the tidal tails produced by interacting gas-rich galaxies,…

Astrophysics of Galaxies · Physics 2015-05-20 S. Recchi , P. Kroupa , S. Ploeckinger

HST trigonometric distances, photometric metallicities, isochronic ages from the second revised version of the Geneva--Copenhagen survey, and uniform spectroscopic Fe and Mg abundances from our master catalog are used to construct and…

Astrophysics of Galaxies · Physics 2015-05-28 V. A. Marsakov , V. V. Koval' , T. V. Borkova , M. V. Shapovalov

By means of high-resolution cosmological hydrodynamical simulations of Milky Way-like disc galaxies, we conduct an analysis of the associated stellar metallicity distribution functions (MDFs). After undertaking a kinematic decomposition of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 F. Calura , B. K. Gibson , L. Michel-Dansac , G. S. Stinson , M. Cignoni , A. Dotter , K. Pilkington , E. L. House , C. B. Brook , C. G. Few , J. Bailin , H. M. P. Couchman , J. Wadsley , .

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…

Astrophysics of Galaxies · Physics 2017-04-06 Ralph Schönrich , Paul McMillan

Models of the chemical evolution of our Galaxy are extended to include radial migration of stars and flow of gas through the disc. The models track the production of both iron and alpha elements. A model is chosen that provides an excellent…

Astrophysics · Physics 2015-05-13 Ralph Schoenrich , James Binney

We derive a new metallicity distribution of G dwarfs in the solar neighbourhood, using uvby photometry and up-to-date parallaxes. Our distribution comprises 287 G dwarfs within 25 pc from the Sun, and differs considerably from the classic…

Astrophysics · Physics 2015-06-24 Helio J. Rocha-Pinto , Walter J. Maciel

We determine the metallicity distribution function (MDF) of the Galactic halo by means of a sample of 1638 metal-poor stars selected from the Hamburg/ESO objective-prism survey (HES). The sample was corrected for minor biases introduced by…