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Related papers: Two-Component Galactic Bulge Probed with Renewed G…

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We aim to quantify the chemical and kinematical properties of the Galactic disks with a sample of 119,558 giant stars having abundances and 3D velocities taken or derived from the APOGEE DR17 and Gaia EDR3 catalogs. The Gaussian Mixture…

Astrophysics of Galaxies · Physics 2022-04-20 Guozhen Hu , Zhengyi Shao

The elemental abundance structure of the Galactic disc has been extensively studied in the solar neighbourhood using long-lived stars such as F and G dwarfs or K and M giants. These are stars whose atmospheres preserve the chemical…

Astrophysics of Galaxies · Physics 2015-05-18 T. Bensby , A. Alves-Brito , M. S. Oey , D. Yong , J. Meléndez

We investigate the properties of the stellar populations of model galaxies as a function of galaxy evolutionary history and angular momentum content. We use the new semi-analytic model presented in Tonini et al. (2016). This new model…

Astrophysics of Galaxies · Physics 2017-01-11 Chiara Tonini , Simon J. Mutch , J. Stuart B. Wyithe , Darren J. Croton

Using 3-dimensional hydrodynamical simulations of isolated dwarf spheroidal galaxies (dSphs), we undertake an analysis of the chemical properties of their inner regions, identifying the respective roles played by Type Ia (SNe Ia) and Type…

Astrophysics · Physics 2009-11-13 A. Marcolini , A. D'Ercole , G. Battaglia , B. K. Gibson

We investigate the origin of the galaxy color-concentration bimodality at the bright-end of the luminosity function (M(B) - 5 log h < -18 mag) with regard to the bulge-disc nature of galaxies. Via (2D) surface brightness profile modeling…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-25 Ewan Cameron , Simon P. Driver , Alister W. Graham , Jochen Liske

It is well established that the chemical structure of the Milky Way exhibits a bimodality with respect to the $\alpha$-enhancement of stars at a given [Fe/H]. This has been studied largely based on a bulk $\alpha$ abundance, computed as a…

Astrophysics of Galaxies · Physics 2019-09-20 Kirsten Blancato , Melissa Ness , Kathryn V. Johnston , Jan Rybizki , Megan Bedell

One of the conundrums in extragalactic astronomy is the discrepancy in observed metallicity distribution functions (MDFs) between the two prime stellar components of early-type galaxies-globular clusters (GCs) and halo field stars. This is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Suk-Jin Yoon , Sang-Yoon Lee , John P. Blakeslee , Eric W. Peng , Sangmo T. Sohn , Jaeil Cho , Hak-Sub Kim , Chul Chung , Sooyoung Kim , Young-Wook Lee

A new view on our Galaxy has recently emerged, with large consequences on its formation scenarios. Not only new dwarf satellites have been detected, still orbiting and tidally disrupting, but also a multitude of stellar streams or tidal…

Astrophysics · Physics 2007-05-23 F. Combes

We derive ages, metallicities and [alpha/Fe] ratios from the integrated spectra of 23 globular clusters in M31, by employing multivariate fits to two stellar population models. In parallel we analyze spectra of 21 Galactic globular clusters…

The abundances of iron and oxygen are homogeneously determined in a sample of 523 nearby (d<150 pc) FGK disk and halo stars with metallicities in the range -1.5<[Fe/H]<0.5. The oxygen abundances were inferred from a restricted non-LTE…

Astrophysics · Physics 2009-11-13 I. Ramirez , C. Allende Prieto , D. L. Lambert

In recent years, increasing attention has been devoted to semi empirical, data-driven models to tackle some aspects of the complex and still largely debated topic of galaxy formation and evolution. We here present a new semi empirical model…

Astrophysics of Galaxies · Physics 2023-07-26 Lumen Boco , Andrea Lapi , Francesco Shankar , Hao Fu , Francesco Gabrielli , Alex Sicilia

Lithium abundances are presented for 91 dwarf and subgiant stars in the Galactic bulge. The analysis is based on line synthesis of the 7Li line at 6707 {\AA} in high-resolution spectra obtained during gravitational microlensing events, when…

Astrophysics of Galaxies · Physics 2020-02-26 T. Bensby , S. Feltzing , J. C. Yee , J. A. Johnson , A. Gould , M. Asplund , J. Meléndez , S. Lucatello

Numerical simulations of double-barred galaxies predict the build-up of different structural components (e.g., bulges, inner discs) in the central regions of disc galaxies. In those simulations, inner bars have a prominent role in the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 A. de Lorenzo-Cáceres , J. Falcón-Barroso , A. Vazdekis

Context. Bulges, located at the central regions of galaxies, are complex structures, expected to be shaped by the physical processes involved in the assembly history of their host galaxy, such as gravitational collapse, mergers,…

We show that the bulge and the disk of the Milky Way (MW) at R$\lesssim$7~kpc are well described by a unique chemical evolution and a two-phase star-formation history (SFH). We argue that the populations within this inner disk, not the…

Astrophysics of Galaxies · Physics 2018-10-17 Misha Haywood , Paola Di Matteo , Matthew Lehnert , Owain Snaith , Francesca Fragkoudi , Sergey Khoperskov

We investigate the metal enrichment of the intracluster medium (ICM) in the framework of hierarchical models of galaxy formation. We calculate the formation and evolution of galaxies and clusters using a semi-analytical model which includes…

The origin of the high-alpha component of the Galactic bulge remains debated, unlike the bar-driven origin of the low-alpha bulge. We examine the metallicity-dependent dynamical properties of high-[Mg/Fe] stars in the bar region, using…

Astrophysics of Galaxies · Physics 2025-09-19 Aakash Pandey , Ortwin Gerhard

The central part of the Galaxy host a multitude of stellar populations, including the spheroidal bulge stars, stars moved to the bulge through secular evolution of the bar, inner halo, inner thick disk, inner thin disk, as well as debris…

The Small Magellanic Cloud is a close, irregular galaxy that has experienced a complex star formation history due to the strong interactions occurred both with the Large Magellanic Cloud and the Galaxy. Despite its importance, the chemical…

Solar and Stellar Astrophysics · Physics 2015-06-17 A. Mucciarelli

We study the origin of the stellar $\alpha$-element-to-iron abundance ratio, $[\alpha/\mathrm{Fe}]_{\ast}$, of present-day central galaxies, using cosmological, hydrodynamical simulations from the Evolution and Assembly of GaLaxies and…

Astrophysics of Galaxies · Physics 2016-06-08 Marijke C. Segers , Joop Schaye , Richard G. Bower , Robert A. Crain , Matthieu Schaller , Tom Theuns
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