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The total deuterium abundance [D/H] in the universe is set by just two processes: the creation of deuterium in Big Bang Nucleosynthesis at an abundance of [D/H]$=2.58\pm0.13\times10^{-5}$, and its destruction within stellar interiors.…

The predictions of the abundances of D and \he3 from Big Bang Nucleosynthesis (BBN) and recent observations of these two isotopes suggest the need to develop new chemical evolution models. In particular, we examine the role of an early…

Astrophysics · Physics 2016-08-15 Sean Scully , Michel Cassé , Keith A. Olive , Elisabeth Vangioni-Flam

We consider the depletion of primordial deuterium in the interior of substellar objects as a function of mass, age and absolute magnitude in several photometric passbands. We characterize potential spectroscopic signatures of deuterium in…

Astrophysics · Physics 2009-10-31 G. Chabrier , I. Baraffe , F. Allard , P. Hauschildt

The primordial abundance of deuterium produced during Big Bang Nucleosynthesis (BBN) depends sensitively on the universal ratio of baryons to photons, an important cosmological parameter probed independently by the Cosmic Microwave…

Astrophysics of Galaxies · Physics 2015-05-13 Gary Steigman

Of the light elements, the primordial abundance of deuterium, (D/H)_p, provides the most sensitive diagnostic for the cosmological mass density parameter Omega_B. Recent high redshift (D/H) measurements are highly discrepant, although this…

Quasar absorption lines now permit a direct probe of deuterium abundances in primordial material, with the best current estimate $ (D/H)=1.9\pm 0.4 \times 10^{-4}$. If this is the universal primordial abundance $(D/H)_p$, Standard Big Bang…

Astrophysics · Physics 2008-02-03 Craig J. Hogan

The current status of extragalactic deuterium abundance is discussed using two examples of `low' and `high' D/H measurements. We show that the discordance of these two types of D abundances may be a consequence of the spatial correlations…

Astrophysics · Physics 2007-05-23 Sergei A. Levshakov , Fumio Takahara , Wilhelm H. Kegel

As a tool to interpret nearby and high redshift galaxy data from optical to K-band we present our chemically consistent spectrophotometric evolutionary synthesis models. These models take into account the increasing initial metallicity of…

Astrophysics · Physics 2009-10-31 C. S. Möller , U. Fritze-v. Alvensleben , K. J. Fricke , D. Calzetti

We report on a survey of \nh2d towards protostellar cores in low-mass star formation and quiescent regions in the Galaxy. Twenty-three out of thirty-two observed sources have significant ($\gsim 5\sigma$) \nh2d emission. Ion-molecule…

Astrophysics · Physics 2009-11-06 Ronak Y. Shah , H. Alwyn Wootten

Because of their low gravitational energies dwarf galaxies are greatly exposed to energetical influences by the interstellar medium, like e.g.\ stellar radiation, winds or explosions, or by their environment. While the metallicity depletion…

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

We review and update some aspects of deuterium chemistry in the post-recombination Universe with particular emphasis on the formation and destruction of HD. We examine in detail the available theoretical and experimental data for the…

Astrophysics · Physics 2009-11-07 D. Galli , F. Palla

In this work we present the predictions of a modified version of the ``two-infall model'' (Chiappini et al. 1997) for the evolution of 3He, 4He and D in the solar vicinity, as well as their distributions along the Galactic disk. In…

Astrophysics · Physics 2007-05-23 Cristina Chiappini , Francesca Matteucci

The early chemical evolution of the Galaxy and the Universe is vital to our understanding of a host of astrophysical phenomena. Since the most metal-poor Galactic stars (with metallicities down to [Fe/H]\sim-5.5) are relics from the…

Astrophysics of Galaxies · Physics 2015-05-30 Anna Frebel

The evolution of the cosmic dust content and the cycle between metals and dust in the interstellar medium (ISM) play a fundamental role in galaxy evolution. The chemical enrichment of the Universe can be traced through the evolution of the…

We consider the galactic evolutionary history of \he3 in models which deplete deuterium by as much as a factor of 2 to $\sim$ 15 from its primordial value to its present day observed value in the ISM. We show that when \he3 production in…

We review the status of the measurements of the deuterium abundance from the local interstellar medium to the solar system and high redshifts absorbers toward quasars. We present preliminary results toward a white dwarf and a QSO. We…

Astrophysics · Physics 2016-08-30 A. Vidal-Madjar , R. Ferlet , M. Lemoine

The observed cosmic abundances of light elements are most consistent with each other, and with the predictions of big bang nucleosynthesis,if, contrary to the usual assumption, galactic chemical evolution reduces $(D+\ ^3He)/H$ with time.…

Astrophysics · Physics 2009-10-22 Craig J. Hogan

I summarize the stellar side of the cosmological lithium problem(s). Evidence from independent studies is accumulating and indicates that stars may very well be fully responsible for lowering their surface lithium from the predicted…

Solar and Stellar Astrophysics · Physics 2024-06-17 A. J. Korn

The chemical evolution in high-mass star-forming regions is still poorly constrained. Studying the evolution of deuterated molecules allows to differentiate between subsequent stages of high-mass star formation regions due to the strong…

Astrophysics of Galaxies · Physics 2015-07-15 Th. Gerner , Y. Shirley , H. Beuther , D. Semenov , H. Linz , T. Abertsson , Th. Henning

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