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Related papers: Stellar populations in $\omega$ Centauri: a multiv…

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We perform a combined analysis of stellar kinematics and line-of-sight accelerations of millisecond pulsars to investigate the mass contents of Omega Centauri. We consider multiple mass components: the visible photometric distribution, a…

Astrophysics of Galaxies · Physics 2025-01-15 Andrés Bañares-Hernández , Francesca Calore , Jorge Martin Camalich , Justin I. Read

We have compiled a sample of globular clusters with high quality stellar abundances from the literature to compare to the chemistries of stars in the Galaxy and those in dwarf spheroidal galaxies. Of the 45 globular clusters examined, 29…

Astrophysics · Physics 2008-11-26 Barton J. Pritzl , Kim A. Venn , Mike J. Irwin

Globular clusters (GCs) are important donors to the build-up of the Milky Way (MW) stellar halo, having contributed at the ten percent level over the Galactic history. Stars that originated from the second generation of dissolved or…

We study the chemical properties of the stellar populations in eight simulations of the formation of Milky-Way mass galaxies in a LCDM Universe. Our simulations include metal-dependent cooling and an explicitly multiphase treatment of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Patricia B. Tissera , Simon D. M. White , Cecilia Scannapieco

We analyze spectra of 18 stars belonging to the faintest subgiant branch in omega Centauri (the SGB-a), obtained with GIRAFFE@VLT at a resolution o R~17000 and a S/N ratio between 25 and 50. We measure abundances of Al, Ba, Ca, Fe, Ni, Si,…

Astrophysics of Galaxies · Physics 2015-05-30 E. Pancino , A. Mucciarelli , P. Bonifacio , L. Monaco , L. Sbordone

In this work, we study the formation and chemical evolution of the Galactic bulge with particular focus on the abundance pattern ([Mg/Fe] vs. [Fe/H]), metallicity and age distribution functions. We consider detailed chemical evolution…

Chemical abundances in the X-ray halos (also known as the intracluster medium, ICM) of clusters and groups of galaxies can be measured via prominent emission line features in their X-ray spectra. Elemental abundances are footprints of…

High Energy Astrophysical Phenomena · Physics 2018-12-19 Junjie Mao , J. de Plaa , J. S. Kaastra , Ciro Pinto , Liyi Gu , F. Mernier , Hong-Liang Yan , Yu-Ying Zhang , H. Akamatsu

There is a growing body of evidence for the presence of multiple stellar populations in some globular clusters, including NGC 1851. For most of these peculiar globular clusters, however, the evidence for the multiple red giant-branches…

Astrophysics of Galaxies · Physics 2014-11-20 Sang-Il Han , Young-Wook Lee , Seok-Joo Joo , Sangmo Tony Sohn , Suk-Jin Yoon , Hak-Sub Kim , Jae-Woo Lee

Context. With the increasing number of discoveries of globular clusters in the inner Milky Way, the need for spectroscopic confirmation and further investigation of their stellar populations and chemodynamical properties has become crucial.…

Astrophysics of Galaxies · Physics 2024-10-30 Dongwook Lim , Sang-Hyun Chun , Young-Wook Lee , Chul Chung , Andreas J. Koch-Hansen , Seungsoo Hong

We have compiled a sample of 699 stars from the recent literature with detailed chemical abundance information (spanning -4.2 < [Fe/H] < +0.3), and we compute their space velocities and Galactic orbital parameters. We identify members of…

Astrophysics · Physics 2009-11-13 Ian U. Roederer

Metal-poor stars are key for studying the formation and evolution of the Galaxy. Evidence of the early mergers that built up the Galaxy remains in the distributions of abundances, kinematics, and orbital parameters of its stars. Several…

Astrophysics of Galaxies · Physics 2023-09-06 André Rodrigo da Silva , Rodolfo Smiljanic

Abundance trends in heavier elements with evolutionary phase have been shown to exist in the globular cluster NGC 6752 [Fe/H]=-1.6. These trends are a result of atomic diffusion and additional (non-convective) mixing. Studying such trends…

Solar and Stellar Astrophysics · Physics 2014-09-05 Pieter Gruyters , Thomas Nordlander , Andreas J. Korn

A large number of spectroscopic studies have provided evidence of the presence of multiple populations in globular clusters by revealing patterns in the stellar chemical abundances. This paper is aimed at studying the origin of these…

Astrophysics of Galaxies · Physics 2015-05-18 Annibale D'Ercole , Francesca D'Antona , Paolo Ventura , Enrico Vesperini , Stephen L. W. McMillan

[ABRIDGED] $\omega$ Centauri (NGC 5139) contains large numbers of variable stars of different types and, in particular, more than a hundred RR Lyrae stars. We have conducted a variability survey of $\omega$ Cen in the NIR, using ESO's 4.1m…

Solar and Stellar Astrophysics · Physics 2015-05-13 C. Navarrete , R. Contreras Ramos , M. Catelan , C. M. Clement , F. Gran , J. Alonso-García , R. Angeloni , M. Hempel , I. Dékány , D. Minniti

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

The radially averaged metallicity distribution of the ISM and the young stellar population of a sample of 20 disk galaxies is investigated by means of an analytical chemical evolution model which assumes constant ratios of galactic wind…

We present [Fe/H] and [Ca/Fe] of $\sim600$ red giant branch (RGB) members of the globular cluster $\omega$ Centauri. We collect medium-resolution ($R\sim2000$) spectra using the Blanco 4 m telescope at the Cerro Tololo Inter-American…

Astrophysics of Galaxies · Physics 2017-09-27 Deokkeun An , Young Sun Lee , Jae In Jung , Soo-Chang Rey , Jaehyon Rhee , Jae-Woo Lee , Young-Wook Lee , Young Hoon Joe

ABRIDGED) We revise the formation of Galactic GCs by adding the detailed chemical composition of their different stellar generations (from 1200 giants in 19 GCs) to their global parameters. We propose to identify as GCs those showing the…

To understand the history and formation mechanisms of galaxies it is crucial to determine their current multidimensional structure. Here we focus on stellar population properties, such as metallicity and [$\alpha$/Fe] enhancement. We devise…

Astrophysics of Galaxies · Physics 2021-03-24 Grzegorz Gajda , Ortwin Gerhard , Matías Blaña , Ling Zhu , Juntai Shen , Roberto P. Saglia , Ralf Bender

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