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Related papers: Composition of the Galactic bulge

200 papers

To better understand the origin and evolution of the Milky Way bulge, we have conducted a survey of bulge red giant branch and clump stars using the HERMES spectrograph on the Anglo-Australian Telescope. We targeted ARGOS survey stars with…

Astrophysics of Galaxies · Physics 2019-05-01 L. Duong , M. Asplund , D. M. Nataf , K. C. Freeman , M. Ness , L. M. Howes

Context. The formation and evolution of the Milky Way bulge is still largely an unanswered question. One of the most essential observables needed in its modelling are the metallicity distribution and the trends of the alpha elements as…

Astrophysics of Galaxies · Physics 2014-12-10 N. Ryde , M. Schultheis

Manganese is mainly produced in type II SNe during explosive silicon burning, in incomplete Si-burning regions, and depends on several nucleosynthesis environment conditions, such as mass cut beween the matter ejected and falling back onto…

Astrophysics of Galaxies · Physics 2015-06-17 B. Barbuy , V. Hill , M. Zoccali , D. Minniti , A. Renzini , S. Ortolani , A. Gomez , M. Trevisan , N. Dutra

The structure, formation, and evolution of the Milky Way bulge is a matter of debate. Important diagnostics for discriminating between bulge models include alpha-abundance trends with metallicity, and spatial abundance and metallicity…

Astrophysics of Galaxies · Physics 2015-12-23 N. Ryde , M. Schultheis , V. Grieco , F. Matteucci , R. M. Rich , S. Uttenthaler

We present abundance ratio estimates of individual elements, namely C, N, Na, and the so-called alpha elements, Mg, O, Si, Ca, and Ti, for the bulge of M31. The analysis is based on long-slit, high-quality spectroscopy of the bulge, taken…

Astrophysics of Galaxies · Physics 2025-02-26 F. La Barbera , A. Vazdekis , A. Pasquali

Based on high-resolution spectra obtained during gravitational microlensing events we present a detailed elemental abundance analysis of 32 dwarf and subgiant stars in the Galactic bulge. [ABRIDGED], we now have 58 microlensed bulge dwarfs…

Recent theoretical yields and chemical evolution models demonstrate that intermediate-mass AGB stars cannot reproduce the observed abundance distributions of O, Na, Mg, and Al. As a further observational test of this finding, we present…

Observations of the stellar content of the Milky Way's bulge helps to understand the stellar content and evolution of distant galaxies. In this brief overview I will first highlight some recent work directed towards measuring the history of…

Astrophysics · Physics 2007-05-23 Jay A. Frogel

We present a high-resolution spectrum of a microlensed G dwarf in the Galactic bulge with spectroscopic temperature T_eff = 5600 +/- 180 K. This I~21 mag star was magnified by a factor ranging from 1160 to 1300 at the time of observation.…

Solar and Stellar Astrophysics · Physics 2014-11-20 Courtney R. Epstein , Jennifer A. Johnson , Subo Dong , Andrzej Udalski , Andrew Gould , George Becker

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

The accurate O, Mg and Fe abundances derived in previous papers of this series from a homogenous reanalysis of high quality data for a large sample of stars are combined with stellar kinematics in order to discuss the history of star…

Astrophysics · Physics 2007-05-23 Raffaele Gratton , Eugenio Carretta , Francesca Matteucci , Chris Sneden

We have derived abundances of O, Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Fe, Ni and Ba for 43 metal-poor field stars in the solar neighbourhood with iron abundances [Fe/H] ranging from -0.4 to -3.0. Total abundance errors are estimated to about…

We present a detailed study of the composition of 20 M giants in the Galactic center with 15 of them confirmed to be in the Nuclear Star Cluster. As a control sample we have also observed 7 M giants in the Milky Way Disk with similar…

Observations of the stellar content of the bulge of the Milky Way can provide critical guidelines for the interpretation of observations of distant galaxies, in particular for understanding their stellar content and evolution. In this brief…

Astrophysics · Physics 2009-10-31 Jay A. Frogel

The chemical abundances measured in stars of the Galactic bulge offer an unique opportunity to test galaxy formation models as well as impose strong constraints on the history of star formation and stellar nucleosynthesis. The aims of this…

Astrophysics of Galaxies · Physics 2015-05-20 Gabriele Cescutti , Francesca Matteucci

We present deep near-IR photometry for Galactic bulge stars in Baade's Window, $(l,b) = (1.0\deg, -3.9\deg),$ and another minor axis field at $(l,b) = (0^\circ,-6^\circ)$. We combine our data with previously published photometry and…

Astrophysics · Physics 2016-08-30 Glenn P. Tiede , Jay A. Frogel , D. M. Terndrup

We use our new, flux-calibrated stellar population model of absorption-line indices to derive ages, metallicities, and various element abundance ratios from integrated light spectroscopy of galactic globular clusters. The ages agree well…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Daniel Thomas , Jonas Johansson , Claudia Maraston

We present the results of the first analysis of high dispersion spectra of four red HB stars in the metal rich globular cluster NGC 6528, located in Baade's Window. We find that the mean [Fe/H] for NGC 6528 is +0.07+-0.01 dex (error of the…

Astrophysics · Physics 2009-11-06 Eugenio Carretta , Judith G. Cohen , Raffaele G. Gratton , Bradford B. Behr

We have made observations with the Keck I telescope and HIRES at a resolution of $\sim$45,000 of five nearly identical stars at the turn-off of the metal-rich globular cluster M 71. Our mean Fe abundance, [Fe/H]=-0.80 +-0.02, is in…

This is the second in a series of papers in which we analyze spectra of over 400 K and M giants in Baade's Window, including most of the stars with proper motions measured by Spaenhauer et al. [AJ, 103, 297 (1992)]. In our first paper, we…

Astrophysics · Physics 2014-10-13 Elaine M. Sadler , R. Michael Rich , D. M. Terndrup