English
Related papers

Related papers: Chemical Evolution of CNO abundances

200 papers

We interpret the peculiar super-solar nitrogen abundance recently reported by the James Webb Space Telescope observations for GN-z11 ($z=10.6$) using our state-of-the-art chemical evolution models. The observed CNO ratios can be…

Astrophysics of Galaxies · Physics 2024-01-23 Chiaki Kobayashi , Andrea Ferrara

Inhomogeneous chemical evolution models of galaxies which try to reproduce the scatter seen in element-to-iron ratios of metal-poor halo stars are heavily dependent on theoretical nucleosynthesis yields of core-collapse supernovae. Hence…

Astrophysics · Physics 2009-11-06 D. Argast , M. Samland , F. -K. Thielemann , O. E. Gerhard

Aims: We test predictions of evolution models on mixing of CNO-cycled products in massive stars from a fundamental perspective. Relative changes within the theoretical C:N:O abundance ratios and the buildup of helium are compared with…

Solar and Stellar Astrophysics · Physics 2010-05-14 N. Przybilla , M. Firnstein , M. F. Nieva , G. Meynet , A. Maeder

The trends of chemical abundances and abundance ratios observed in stars of different ages, kinematics, and metallicities bear the imprints of several physical processes that concur to shape the host galaxy properties. By inspecting these…

Recent models of galactic chemical evolution account for updated evolutionary models of massive stars (with special emphasis on stellar winds) and for the effects of intermediate mass and massive binaries. The results are summarised. We…

Astrophysics · Physics 2016-01-27 D. Vanbeveren , E. De Donder

CNO abundances in galaxies bear on issues of galactic evolution as well as stellar evolution and nucleosynthesis. Knowledge about them in dwarf and spiral galaxies depends mainly on emission lines from H II regions, with information from…

Astrophysics · Physics 2007-05-23 B. E. J. Pagel

In order to investigate the possible influence of rotation on the efficiency of the first dredge-up we determined atmospheric parameters, masses, and abundances of carbon, nitrogen, and oxygen in a sample of evolved intermediate mass stars.…

Astrophysics · Physics 2009-11-11 R. Smiljanic , B. Barbuy , J. R. De Medeiros , A. Maeder

We study the sensitivity of presupernova evolution and supernova nucleosynthesis yields of massive stars to variations of the initial composition. We use the solar abundances from Lodders (2009), and compute two different initial stellar…

Solar and Stellar Astrophysics · Physics 2024-10-23 Christopher West , Alexander Heger , Benoit Cote , Lev Serxner , Haoxuan Sun

We present a double-blind analysis of high-dispersion spectra of seven red giant members of the Bo\"{o}tes I ultra-faint dwarf spheroidal galaxy, complemented with re-analysis of a similar spectrum of an eighth member star. The stars cover…

Astrophysics of Galaxies · Physics 2015-06-12 Gerard Gilmore , John E. Norris , Lorenzo Monaco , David Yong , Rosemary F. G. Wyse , D. Geisler

We present first results of an implementation of chemical evolution in a cosmological hydrodynamical code, focusing the analysis on the effects of cooling baryons according to their metallicity. We found that simulations with primordial…

Astrophysics · Physics 2007-05-23 Patricia B. Tissera , Cecilia Scannapieco

We find a new analytical solution for the chemical evolution equations, taking into account the delayed contribution of all low and intermediate mass stars (LIMS) as one representative star that enriches the interstellar medium.This…

Astrophysics · Physics 2008-07-09 I. Franco , L. Carigi

I review the current data on abundances in irregular galaxies, with special emphasis on recent results on C/O and Si/O from observations with the Hubble Space Telescope. The abundance data for He, C, N, and O in irregular galaxies is…

Astrophysics · Physics 2008-02-03 Don Garnett

We present a new grid of stellar models and isochrones for old stellar populations, covering a large range of [Fe/H] values, for an heavy element mixture characterized by CNONa abundance anticorrelations as observed in Galactic globular…

Solar and Stellar Astrophysics · Physics 2011-02-11 A. Pietrinferni , S. Cassisi , M. Salaris , S. Percival , J. W. Ferguson

A LiBeB evolution model including Galactic Cosmic Ray nucleosynthesis, the $\nu$-process, novae, AGB and C-stars is presented. We have included Galactic Cosmic Ray Nucleosynthesis (GCRN) in a complete Chemical Evolution Model that takes…

Astrophysics · Physics 2016-11-03 Andreu Alibes , Javier Labay , Ramon Canal

The main objective of the present work is to ckeck if the star formation efficiency plays a relevant role in the evolution of the relative abundance N/O. We analyze the evolution of the nitrogen-to-oxygen ratio as predicted by a set of…

Astrophysics · Physics 2016-08-15 M. Mollá , J. M. Vílchez , M. Gavilán , A. I. Díaz

Linear [Q/H]-[O/H] relations, Q = Na, Mg, Si, Ca, Ti, Cr, Fe, Ni, are inferred from a sample (N=67) of recently studied FGK-type dwarf stars in the solar neighbourhood including different populations. Regression line slope and intercept…

Astrophysics of Galaxies · Physics 2013-12-24 R. Caimmi

Determinations of the \he3 concentrations in Galactic matter serve to impose interesting and important constraints both on cosmological models and on models of Galactic chemical evolution. At present, observations of \he3 in the solar…

Astrophysics · Physics 2009-09-15 Sean T. Scully , Michel Casse , Keith A. Olive , D. N. Schramm , J. Truran , E. Vangioni-Flam

One of the complexities in modelling integrated spectra of stellar populations is the effect of interacting binary stars besides type Ia supernovae (SNeIa). These include common envelope systems, CVs, novae, and are usually ignored in…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 A. E. Sansom , R. G. Izzard , P. Ocvirk

Chemical evolution of galaxies brings together ideas on stellar evolution and nucleosynthesis with theories of galaxy formation, star formation and galaxy evolution, with all their associated uncertainties. In a new perspective brought…

Astrophysics · Physics 2009-10-31 B. E. J. Pagel

The first part of this paper deals with the impact of nonsolar and - for late-type, dwarf, and high redshift galaxies - generally subsolar abundances on the interpretation of observational data for starburst galaxies. It points out the…

Astrophysics · Physics 2007-05-23 U. Fritze-v. Alvensleben
‹ Prev 1 3 4 5 6 7 10 Next ›