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Related papers: The age of the Galaxy's thick disk

200 papers

I review different methods devised to derive the age of the Galactic Disk, namely the Radio-active Decay (RD), the Cool White Dwarf Luminosity Function (CWDLF), old opne clusters (OOC) and the Color Magnitude Diagram (CMD) of the stars in…

Astrophysics · Physics 2016-01-27 Giovanni Carraro

We highlight some results from our detailed abundance analysis study of 703 kinematically selected F and G dwarf stars in the solar neighbourhood. The analysis is based on spectra of high-resolution (R=45000 to 110000) and high…

Astrophysics of Galaxies · Physics 2015-05-30 T. Bensby , S. Feltzing

We have investigated the abundance of several chemical elements in two large stellar samples kinematically representative of the thin and the thick disks of the Galaxy. Chemical, kinematical and age data have been collected from high…

Astrophysics · Physics 2007-05-23 Pascal Girard , Caroline Soubiran

We present a detailed analysis of the white dwarf luminosity functions derived from the local 40 pc sample and the deep proper motion catalog of Munn et al (2014, 2017). Many of the previous studies ignored the contribution of thick disk…

We have obtained high-resolution spectra and carried out a detailed elemental abundance analysis for a new sample of 899 F and G dwarf stars in the Solar neighbourhood. The results allow us to, in a multi-dimensional space consisting of…

Astrophysics of Galaxies · Physics 2010-04-27 T. Bensby , S. Feltzing

In local disk galaxies such as our Milky Way, older stars generally inhabit a thicker disk than their younger counterparts. Two competing models have attempted to explain this result: one in which stars first form in thin disks that…

We have measured Lick index equivalent widths to derive luminosity weighted stellar ages and metallicities for thin and thick disk dominated regions of 9 edge-on disk galaxies with the ARC 3.5 meter telescope at Apache Point Observatory. In…

Astrophysics · Physics 2009-11-13 Peter Yoachim , Julianne J. Dalcanton

The formation of the extended thin disc is the most spectacular event of our Galaxy in the past $\sim8$\,Gyr. To unveil this process, obtaining precise and accurate stellar ages for a large sample of stars is essential although challenging.…

Astrophysics of Galaxies · Physics 2023-01-20 Wu Yaqian , Xiang Maosheng , Zhao Gang , Chen Yuqin , Bi Shaolan , Li Yaguang

We show that the Galactic thick disk reaches at least solar metallicities, and that it experienced strong chemical enrichment during a period of ~3 Gyr, ending around 8-9 Gyr ago. This finding puts further constraints on the relation and…

Astrophysics · Physics 2010-11-11 T. Bensby , A. R. Zenn , M. S. Oey , S. Feltzing

New ages are computed for stars in the Solar Neighbourhood from the Edvardsson et al. (1993) data set. Distances derived from the Hipparcos parallaxes were adopted to obtain reliable ages (uncertainty less than 12%) for a subset of stars.…

Astrophysics · Physics 2007-05-23 Y. K. Ng , G. Bertelli , G. Carraro , L. Portinari

We analyze high quality abundances data of solar neighborhood stars and show that there are two distinct regimes of [alpha/Fe] versus age which we identify as the epochs of the thick and thin disk formation. A tight correlation between…

Astrophysics of Galaxies · Physics 2015-06-16 M. Haywood , P. Di Matteo , M. Lehnert , D. Katz , A. Gomez

One of the suggested thick disc formation mechanisms is that they were born quickly and in situ from a turbulent clumpy disc. Subsequently, thin discs formed slowly within them from leftovers of the turbulent phase and from material…

Astrophysics of Galaxies · Physics 2021-01-27 S. Comerón

A sample of 229 nearby thick disk stars has been used to investigate the existence of an age-metallicity relation (AMR) in the Galactic thick disk. The results indicate that that there is indeed an age-metallicity relation present in the…

Astrophysics · Physics 2009-11-10 T. Bensby , S. Feltzing , I. Lundstrom

Ages, metallicities, space velocities, and Galactic orbits of stars in the Solar neighbourhood are fundamental observational constraints on models of galactic disk evolution. We aim to consolidate the calibrations of uvby photometry into…

Astrophysics · Physics 2009-11-13 J. Holmberg , B. Nordstrom , J. Andersen

I briefly review the growing evidence that thick stellar disks surround most edge-on disk galaxies. Recent studies show that these extragalactic thick disks have old ages, low metallicities, long scale lengths, and moderately flattened…

Astrophysics · Physics 2007-05-23 Julianne J. Dalcanton , Anil Seth , Peter Yoachim

We have traced the Galactic thick disk to its, to date, highest metallicities. Based on high-resolution spectroscopic observations of 187 F and G dwarf stars that kinematically can be associated either with the thin disk (60 stars) or with…

Astrophysics · Physics 2007-05-23 T. Bensby , A. R. Zenn , M. S. Oey , S. Feltzing

In the Milky Way, the thick disk can be defined using individual stellar abundances, kinematics, or age; or geometrically, as stars high above the mid-plane. In nearby galaxies, where only a geometric definition can be used, thick disks…

Astrophysics of Galaxies · Physics 2016-11-09 Marie Martig , Ivan Minchev , Melissa Ness , Morgan Fouesneau , Hans-Walter Rix

We trace the evolution of eight edge-on star-forming disk galaxies by analyzing stellar population properties of their thin and thick disks. These galaxies have relatively low stellar masses (4~$\times$~10$^9$ to…

Oxygen and carbon are important elements in stellar populations. Their behavior refers to the formation history of the stellar populations. C and O abundances would also obviously influence stellar opacities and the overall metal abundance…

Solar and Stellar Astrophysics · Physics 2016-12-21 Z. S. Ge , S. L. Bi , Y. Q. Chen , T. D. Li , J. K. Zhao , K. Liu , Fergusion J. W. , Y. Q. Wu

The origin of thick disks and their evolutionary connection with thin disks are still a matter of debate. We provide new insights into this topic by connecting the stellar populations of thick disks at redshift $z=0$ with their past…

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