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Related papers: Cosmological evolution of the Nitrogen abundance

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The uncertainties which still plague our understanding of the evolution of the light nuclides D, 3He and 4He in the Galaxy are described. Measurements of the local abundance of deuterium range over a factor of 3. The observed dispersion can…

Astrophysics of Galaxies · Physics 2015-05-14 Donatella Romano

Models of galactic chemical evolution (CEMs) show that the shape of the stellar initial mass function (IMF) and other assumptions regarding star formation affect the resultant abundance gradients in models of late-type galaxies.…

Astrophysics · Physics 2008-08-18 Lars Mattsson

We have investigated the poorly-understood origin of nitrogen in the early Galaxy by determining N abundances in 35 extremely metal-poor halo giants (22 stars have [Fe/H]<-3.0) using the C and O abundances determined in Paper V. Because any…

Spectroscopic observations of distant quasars have resulted in the detection of molecular hydrogen in intervening damped Lyman-alpha absorption clouds (DLAs). We use observations compiled from different experimental groups to show that the…

Astrophysics · Physics 2009-11-10 Stephen J. Curran , John K. Webb , Michael T. Murphy , Robert F. Carswell

The processes that disperse the products of massive stars from their birth sites play a fundamental role in determining the observed abundances. I discuss parameterizations for element dispersal and their roles in chemical evolution, with…

Astrophysics · Physics 2007-05-23 M. S. Oey

Dramatic recent progress in understanding galactic chemical evolution (GCE) has been driven partly by direct observations of the distant past with HST and JWST of stellar abundances from giant high-resolution spectroscopic surveys (APOGEE,…

Astrophysics of Galaxies · Physics 2025-02-19 David H. Weinberg

The description of the tempo-spatial evolution of the composition of cosmic gas on galactic scales is called 'modelling galactic chemical evolution'. It aims to use knowledge about sources of nucleosynthesis and how they change the…

Astrophysics of Galaxies · Physics 2023-10-25 Roland Diehl , Nikos Prantzos

The abundance evolution of interstellar dust species originating from stellar sources and from condensation in molecular clouds in the local interstellar medium of the Milky Way is studied and the input of dust material to the Solar System…

Astrophysics · Physics 2009-11-13 Svitlana Zhukovska , Hans-Peter Gail , Mario Trieloff

Cosmological N-body hydrodynamic computations following atomic and molecular chemistry (e$^-$, H, H$^+$, H$^-$, He, He$^+$, He$^{++}$, D, D$^+$, H$_2$, H$_2^+$, HD, HeH$^+$), gas cooling, star formation and production of heavy elements (C,…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-30 Umberto Maio , Edoardo Tescari

Nitrogen is one of the most abundant metals in the interstellar medium (ISM), and thus it constitutes an excellent test to study a variety of astrophysical environments, ranging from nova to active galactic nuclei. We present a detailed…

High Energy Astrophysical Phenomena · Physics 2021-05-12 Efrain Gatuzz , Javier A. García , Timothy R. Kallman

(Abridged) Estimates of the interstellar deuterium abundance span a wide range of values. Here we study the evolution of deuterium in the framework of successful models for the chemical evolution of the Milky Way able to reproduce the…

Astrophysics · Physics 2009-11-11 Donatella Romano , Monica Tosi , Cristina Chiappini , Francesca Matteucci

We construct a simple, robust model of the chemical evolution of galaxies from high to low redshift, and apply it to published observations of damped Lyman-alpha quasar absorption line systems (DLAs). The elementary model assumes quiescent…

Astrophysics · Physics 2009-10-31 G. P. Mathlin , A. C. Baker , D. K. Churches , M. G. Edmunds

The chemical evolution of distant galaxies cannot be assessed from observations of individual stars, in contrast to the case of nearby galaxies. On the other hand, the study of the interstellar medium (ISM) offers an alternative way to…

Based on a simple, but fairly successful, model of the chemical evolution of the Milky Way disk, we study the evolution of the abundances of the elements He, C, N, O, Ne, Mg, Al, Si, S, Ar and Fe. We use metallicity dependent yields for…

Astrophysics · Physics 2007-05-23 J. L. Hou , N. Prantzos , S. Boissier

A hot plasma is the dominant phase of the interstellar medium of early-type galaxies. Its origin can reside in stellar mass losses, residual gas from the formation epoch, and accretion from outside of the galaxies. Its evolution is linked…

Astrophysics of Galaxies · Physics 2020-03-25 S. Pellegrini , Z. Gan , J. P. Ostriker , L. Ciotti

Recent observations of high-redshift galaxies have revealed starburst galaxies with excessive amounts of nitrogen, well above that expected in standard evolutionary models. The Sunburst Arc galaxy, particularly its young and massive star…

Astrophysics of Galaxies · Physics 2024-09-20 Truman Tapia , Kenji Bekki , Brent Groves

Star-to-star variations in abundances of the light elements carbon, nitrogen, oxygen, and sodium have been observed in stars of all evolutionary phases in all Galactic globular clusters that have been thoroughly studied. The data available…

Astrophysics of Galaxies · Physics 2011-05-26 Sarah L. Martell

We derive empirical constraints on the nucleosynthetic yields of nitrogen by incorporating N enrichment into our previously developed and empirically tuned multi-zone galactic chemical evolution model. We adopt a metallicity-independent…

Astrophysics of Galaxies · Physics 2023-02-01 James W. Johnson , David H. Weinberg , Fiorenzo Vincenzo , Jonathan C. Bird , Emily J. Griffith

Rotation has become an important element in evolutionary models of massive stars, specifically via the prediction of rotational mixing. Here, we study a sample of stars, including rapid rotators, to constrain such models and use nitrogen…

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