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Related papers: The Milky Way's middle-aged inner ring

200 papers

We analyse a sample of 507 evolved stars in the inner galactic Plane. We derive average ages for subsets of this sample and use those sets as beacons for the evolution of the Galaxy. In the Bulge the oldest OH/IR stars in the plane are 7.5…

Astrophysics · Physics 2016-08-30 M. Sevenster

We show for the first time, that a fully cosmological hydrodynamical simulation can reproduce key properties of the innermost region of the Milky Way. Our high resolution simulation matches the profile and kinematics of the Milky Way's…

Astrophysics of Galaxies · Physics 2018-07-25 Tobias Buck , Melissa K. Ness , Andrea V. Macciò , Aura Obreja , Aaron A. Dutton

Stellar ages are a crucial component to studying the evolution of the Milky Way. Using Gaia DR2 distance estimates, it is now possible to estimate stellar ages for a larger volume of evolved stars through isochrone matching. This work…

Observations of the Milky Way's low-$\alpha$ disk show that at fixed metallicity, [Fe/H], several element abundance, [X/Fe], correlate with age, with unique slopes and small scatters around the age-[X/Fe] relations. In this study, we turn…

The kinematics of the Milky Way disc as a function of age are well measured at the solar radius, but have not been studied over a wider range of Galactocentric radii. Here, we measure the kinematics of mono-age, mono-$\mathrm{[Fe/H]}$…

We present a detailed elemental abundance study of 90 F and G dwarf, turn-off and subgiant stars in the Galactic bulge. Based on high-resolution spectra acquired during gravitational microlensing events, stellar ages and abundances for 11…

The inner $\sim5$ kiloparsec (kpc) region of the Milky Way is complex. Unravelling the evolution of the Galaxy requires precise understanding of the formation of this region. We report a study focused on disentangling the inner Galaxy ($r <…

Astrophysics of Galaxies · Physics 2024-02-14 Danny Horta , Michael S. Petersen , Jorge Peñarrubia

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 spatial distribution of mono-abundance populations (MAPs, selected in [Fe/H] and [Mg/Fe]) reflect the chemical and structural evolution in a galaxy and impose strong constraints on galaxy formation models. In this paper, we use APOGEE…

In the age of high-resolution spectroscopic stellar surveys of the Milky Way, the number of stars with detailed abundances of multiple elements is rapidly increasing. These elemental abundances are directly influenced by the evolutionary…

The formation of our Milky Way can be parsed qualitatively into different phases that resulted in its structurally different stellar populations: the halo and the disk components. Revealing a quantitative overall picture of the Galactic…

Astrophysics of Galaxies · Physics 2022-03-24 Maosheng Xiang , Hans-Walter Rix

We conduct a quantitative analysis of the star formation history (SFH) of the Milky Way's bulge by exploiting the constraining power of its stellar [Fe/H] and [Mg/Fe] distribution functions. Using APOGEE data, we confirm the…

The Milky Way is a barred galaxy whose central bulge has a box/peanut shape and consists of multiple stellar populations with different orbit distributions. This review describes dynamical and chemo-dynamical equilibrium models for the…

Astrophysics of Galaxies · Physics 2018-08-22 Ortwin Gerhard

Numerous studies of integrated starlight, stellar counts, and kinematics have confirmed that the Milky Way is a barred galaxy. However, far fewer studies have investigated the bar's stellar population properties, which carry valuable…

Very metal-poor stars contain crucial information on the Milky Way's infancy. In our previous study \citep{Plotnikova_2022} we derived a mean age of $\sim$ 13.7 Gyr for a sample of these stars in the Sun's vicinity. In this work, we…

Astrophysics of Galaxies · Physics 2023-05-31 Anastasiia Plotnikova , Giovanni Carraro , Sandro Villanova , Sergio Ortolani

We have for the first time identified the early stellar disk in the Milky Way by using a combination of elemental abundances and kinematics. Using data from APOGEE DR17 and Gaia we select stars in the Mg-Mn-Al-Fe plane with elemental…

Astrophysics of Galaxies · Physics 2023-06-28 Sofia Feltzing , Diane Feuillet

We have determined detailed elemental abundances and stellar ages for a sample of now 38 microlensed dwarf and subgiant stars in the Galactic bulge. Stars with sub-solar metallicities are all old and have enhanced alpha-element abundances…

Astrophysics of Galaxies · Physics 2012-01-11 T. Bensby , S. Feltzing , A. Gould , J. A. Johnson , M. Asplund , D. Adén , J. Meléndez , J. G. Cohen , I. Thompson , S. Lucatello , A. Gal-Yam

Studying the Milky Way disk structure using stars in narrow bins of [Fe/H] and [alpha/Fe] has recently been proposed as a powerful method to understand the Galactic thick and thin disk formation. It has been assumed so far that these…

Astrophysics of Galaxies · Physics 2017-01-04 I. Minchev , M. Steinmetz , C. Chiappini , M. Martig , F. Anders , G. Matijevic , R. S. de Jong

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

Reconstructing the mass assembly history of the Milky Way relies on obtaining detailed measurements of the properties of many stars in the Galaxy, especially in the stellar halo. One of the most constraining quantities is stellar age, as it…

Astrophysics of Galaxies · Physics 2024-06-11 Danny Horta , Yuxi , Lu , Melissa K. Ness , Mariangela Lisanti , Adrian M. Price-Whelan