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Related papers: Self-enrichment in Omega Centauri

200 papers

We present a stochastic model based on the Monte Carlo technique to study the inhomogeneous chemical evolution of the Galactic halo. In particular, we consider the local enrichment and subsequent mixing of the interstellar gas resulting…

Astrophysics · Physics 2009-10-31 Claudia Travaglio , Daniele Galli , Andreas Burkert

Investigating the chemical homogeneity of stars born from the same molecular cloud at virtually the same time is very important for our understanding of the chemical enrichment of the interstellar medium and with it the chemical evolution…

Chemical abundance data for the Galaxy show a wide dispersion. We try to check if this dispersion may also be found with chemical evolution models as an effect of variations of an Initial Mass Function (IMF) which follows a Poisson's…

Astrophysics · Physics 2016-08-16 J. J. Bazan , M. Molla , & M. Cerviño

We combine an analytic model for anisotropic outflows and galaxy formation with numerical simulations of large-scale structure and halo formation to study the impact of galactic outflows on the evolution of the IGM. We have simulated the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Steeve Pinsonneault , Hugo Martel , Matthew M. Pieri

The chemical abundances of stars in galaxies are a fossil record of the star formation and stellar evolution processes that regulate galaxy formation, including the stellar initial mass function, the fraction and timing of type Ia…

We investigate the origin of the abundance ratios and scatter of the neutron-capture elements Sr, Ba and Eu in the stellar halo of a Milky Way-mass galaxy formed in a hydrodynamical cosmological simulation, and compare them with those of…

Astrophysics of Galaxies · Physics 2022-09-21 Cecilia Scannapieco , Gabriele Cescutti , Cristina Chiappini

Copper abundances are presented for 40 red-giant stars in Omega Cen as well as 15 red-giant members of the globular clusters NGC288, NGC362, NGC3201, NGC6752, and M4. A comparison with the halo field star pattern indicates that, unlike the…

Astrophysics · Physics 2016-08-30 K. Cunha , V. V. Smith , N. B. Suntzeff , J. E. Norris , G. S. Da Costa , B. Plez

We explore the metallicity distribution function (MDF) of red giant stars in Omega Centauri from a catalogue of Washington M, T_2 and DDO51 photometry covering over 1.1 deg^2 outside the cluster core. Using updated calibrations of giant…

This chapter reviews how galactic inflows influence galaxy metallicity. The goal is to discuss predictions from theoretical models, but particular emphasis is placed on the insights that result from using models to interpret observations.…

Astrophysics of Galaxies · Physics 2017-05-31 Kristian Finlator

As building blocks of dust, rocky planets, and even complex life, the chemical elements heavier than hydrogen (H) and helium (He) - called "metals" in astronomy - play an essential role in our Universe and its evolution. Up to Fe and Ni,…

High Energy Astrophysical Phenomena · Physics 2022-11-21 François Mernier , Veronica Biffi

A new formation scenario for omega-Cen is presented, in which omega-Cen has formed from a star cluster complex (= super-cluster). The star-burst which has led to the formation of this cluster of star clusters was triggered by the infall and…

Astrophysics · Physics 2007-05-23 M. Fellhauer

Recent high-resolution simulations of early structure formation have shown that externally enriched halos may form some of the first metal enriched stars. This study utilizes a 1 comoving Mpc$^3$ high-resolution simulation to study the…

Astrophysics of Galaxies · Physics 2021-03-17 William Hicks , Azton Wells , Michael L. Norman , John H. Wise , Britton D. Smith , Brian W. O'Shea

We use cosmological hydrodynamic simulations including galactic feedback based on observations of local starbursts to find a self-consistent evolutionary model capable of fitting the observations of the intergalactic metallicity history as…

Astrophysics · Physics 2009-11-11 Benjamin D. Oppenheimer , Romeel Davé , Kristian Finlator

We present three dimensional hydrodynamical simulations aimed at studying the dynamical and chemical evolution of the interstellar medium (ISM) in isolated dwarf spheroidal galaxies (dSphs). This evolution is driven by the explosion of Type…

Astrophysics · Physics 2009-11-13 Andrea Marcolini , Annibale D'Ercole

The gas-phase metallicity of low-mass galaxies increases with increasing stellar mass ($M_\ast$) and is nearly constant for high-mass galaxies. Theory suggests that this tight mass-metallicity relationship is shaped by galactic outflows…

Astrophysics of Galaxies · Physics 2018-09-12 J. Chisholm , C. Tremonti , C. Leitherer

Gas flows play a fundamental role in galaxy formation and evolution, providing the fuel for the star formation process. These mechanisms leave an imprint in the amount of heavy elements. Thus, the analysis of this metallicity signature…

Astrophysics of Galaxies · Physics 2016-04-20 Morgane Cousin , Véronique Buat , Samuel Boissier , Matthieu Béthermin , Yannick Roehlly , Mathieu Génois

A homogeneous spectroscopic analysis of unevolved and evolved stars in the metal-poor globular cluster NGC 6397 with FLAMES-UVES reveals systematic trends of stellar surface abundances that are likely caused by atomic diffusion. This…

We test whether the universal initial mass function (UIMF) or the integrated galaxial IMF (IGIMF) can be employed to explain the metallicity distribution (MD) of giants in the Galactic bulge. We make use of a single-zone chemical evolution…

Astrophysics · Physics 2009-11-13 Silvia K. Ballero , Pavel Kroupa , Francesca Matteucci

The blue Main Sequence (bMS) of $\omega$ Cen implies a ratio of helium to metal enrichment $\Delta Y/\Delta Z \approx 70$, which is a major enigma. We show that rotating models of low metallicity stars, which account for the anomalous…

Astrophysics · Physics 2009-11-11 André Maeder , Georges Meynet

Spectroscopic surveys of the Galaxy reveal that its disc stars exhibit a spread in $\mathrm{[\alpha/Fe]}$ at fixed $\mathrm{[Fe/H]}$, manifest at some locations as a bimodality. The origin of these diverse, and possibly distinct, stellar…

Astrophysics of Galaxies · Physics 2018-05-02 J. Ted Mackereth , Robert A. Crain , Ricardo P. Schiavon , Joop Schaye , Tom Theuns , Matthieu Schaller