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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

Aims: We aim to investigate the abundances of light deuterium-bearing species such as HD, H2D+ and D2H+ in a gas-grain chemical model including an extensive description of deuterium and spin state chemistry, in physical conditions…

Astrophysics of Galaxies · Physics 2015-06-15 O. Sipilä , P. Caselli , J. Harju

We present new models of the deuterium chemistry in protoplanetary disks, including, for the first time, multiply deuterated species. We use these models to explore whether observations in combination with models can give us clues as to…

Astrophysics · Physics 2011-02-11 K. Willacy

Stars are fossils that retain the history of their host galaxies. Elements heavier than helium are created inside stars and are ejected when they die. From the spatial distribution of elements in galaxies, it is therefore possible to…

Astrophysics of Galaxies · Physics 2023-04-27 Chiaki Kobayashi , Philip Taylor

We have extended our chemical and cosmological galaxy evolution model to calculate the abundance evolution for altogether 16 different elements in spiral galaxies in a chemically consistent way which is a considerable step towards a more…

Astrophysics · Physics 2007-05-23 Ulrich Lindner , Uta Fritze -- von Alvensleben , Klaus J. Fricke

The ultraviolet luminosity evolution of star-forming galaxies is explored from the theoretical point of view, especially focusing on the theory of UV energetics in simple and composite stellar populations and its relationship to the star…

Astrophysics · Physics 2009-11-07 Alberto Buzzoni

The deuterium-to-hydrogen (D/H or 2H/1H) ratio of Martian atmospheric water (~6x standard mean ocean water, SMOW) is higher than that of known sources, requiring planetary enrichment. A recent measurement by NASA's Mars Science Laboratory…

Earth and Planetary Astrophysics · Physics 2022-09-23 Kaveh Pahlevan , Laura Schaefer , Linda T. Elkins-Tanton , Steven J. Desch , Peter R. Buseck

This paper presents the first results from a model for chemical evolution that can be applied to N-body cosmological simulations and quantitatively compared to measured stellar abundances from large astronomical surveys. This model…

Astrophysics of Galaxies · Physics 2015-09-29 Brian D. Crosby , Brian W. O'Shea , Timothy C. Beers , Jason Tumlinson

The Galaxy is in continuous elemental evolution. Since new elements produced by dying stars are delivered to the interstellar medium, the formation of new enerations of stars and planetary systems is influenced by this metal enrichment. We…

Astrophysics of Galaxies · Physics 2019-08-17 Em. M. Penteado , H. M. Cuppen , H. J Rocha-Pinto

High levels of deuterium fraction in N$_2$H$^+$ are observed in some pre-stellar cores. Single-zone chemical models find that the timescale required to reach observed values ($D_{\rm frac}^{{\rm N}_2{\rm H}^+} \equiv {\rm N}_2{\rm D}^+/{\rm…

Solar and Stellar Astrophysics · Physics 2016-12-28 Matthew D. Goodson , Shuo Kong , Jonathan C. Tan , Fabian Heitsch , Paola Caselli

We use high resolution spectra obtained with FUSE and STIS to obtain interstellar column densities of H I, D I, O I, S II, Fe II and P II toward the QSO HE 0226-4110 ( l = 253.4 deg , b = -65.77 deg). We obtain D/H = 21(+8, -6) ppm.…

Astrophysics · Physics 2009-11-13 Blair Savage , Nicolas Lehner , Andrew Fox , Bart Wakker , Kenneth Sembach

Observations have revealed unexpectedly large amounts of dust in high-redshift galaxies and its origin is still much debated. Valiante et al. (2009, MNRAS, 397, 1661) suggested the net stellar dust production of the quasar host galaxy SDSS…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Lars Mattsson

Disentangling the different stages of the star-formation process, in particular in the high-mass regime, is a challenge in astrophysics. Chemical clocks could help alleviating this problem, but their evolution strongly depends on many…

Astrophysics of Galaxies · Physics 2020-01-08 S. Bovino , S. Ferrada-Chamorro , A. Lupi , G. Sabatini , A. Giannetti , D. R. G. Schleicher

Constraints on big bang nucleosynthesis (BBN) and on cosmological parameters from conflicting deuterium observations in different high red-shift QSO systems are discussed. The high deuterium observations by Carswell et al., Songaila et al.,…

Astrophysics · Physics 2008-11-26 N. Hata , G. Steigman , S. Bludman , P. Langacker

Quasar (or QSO) elemental abundances provide unique probes of high-redshift star formation and galaxy evolution. There is growing evidence from both the emission and intrinsic absorption lines that QSO environments have roughly solar or…

Astrophysics · Physics 2009-10-31 Fred Hamann , Gary Ferland

The past century of interstellar dust has brought us from first ignoring it to finding that it plays an important role in the evolution of galaxies. Current observational results in our galaxy provide a complex physical and chemical…

Astrophysics · Physics 2009-10-31 J. Mayo Greenberg , Chuanjian Shen

By means of chemo-photometric models for galaxies of different morhological types, we have carried out a detailed study of the history of element production by spheroidal and dwarf irregular galaxies. Spheroidal galaxies suffer a strong and…

Astrophysics · Physics 2009-11-11 Francesco Calura , Francesca Matteucci

We present unified chemical and spectrophotometric evolutionary synthesis models that allow to describe composite stellar populations in a chemically consistent way. Keeping track of the ISM abundance at birth of each star and using sets of…

Astrophysics · Physics 2020-05-27 U. Fritze-v. Alvensleben

Since stellar populations enhance particular element abundances according to the yields and lifetimes of the stellar progenitors, the chemical evolution of galaxies serves as one of the key tools that allows the tracing of galaxy evolution.…

Astrophysics · Physics 2007-05-23 G. Hensler , A. Rieschick

Primordial abundances of light elements are sensitive to the physics of the early Universe and can directly constrain cosmological quantities, such as the baryon-to-photon ratio $\eta_{10}$, the baryon density and the number of neutrino…

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