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Analyses of spectra obtained with the Far Ultraviolet Spectroscopic Explorer (FUSE) satellite, together with spectra from the Copernicus and IMAPS instruments, reveal an unexplained very wide range in the observed deuterium/hydrogen (D/H)…

Measurements of deuterium in the local interstellar medium have revealed large variations in D/H along different lines of sight. Moreover, recent {\it Far Ultraviolet Spectroscopic Explorer} (FUSE) measurements find D/H to be anticorrelated…

天体物理学 · 物理学 2009-06-23 Tijana Prodanovic , Brian D. Fields

The primordial abundance of deuterium (D/H) yields a measure of the density of baryons in the universe and is an important complement to determinations from cosmic microwave background (CMB) experiments. Indeed, the current small sample of…

天体物理学 · 物理学 2009-11-13 Sara L. Ellison , Jason X. Prochaska , Sebastian Lopez

(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…

天体物理学 · 物理学 2009-11-11 Donatella Romano , Monica Tosi , Cristina Chiappini , Francesca Matteucci

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.…

天体物理学 · 物理学 2009-11-13 Blair Savage , Nicolas Lehner , Andrew Fox , Bart Wakker , Kenneth Sembach

Standard big bang nucleosynthesis (BBNS) promises accurate predictions of the primordial abundances of deuterium, helium-3, helium-4 and lithium-7 as a function of a single parameter. Previous measurements have nearly always been…

天体物理学 · 物理学 2008-02-03 Scott Burles , David Tytler

Observations show that the global deuterium-to-hydrogen ratio (D/H) in the local interstellar medium (ISM) is about 90% of the primordial ratio predicted by big bang nucleosynthesis. The high (D/H)$_{ISM}$ implies that only a small fraction…

星系天体物理 · 物理学 2018-05-15 David H. Weinberg

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…

星系天体物理 · 物理学 2015-05-14 Donatella Romano

Accurate measurements of interstellar deuterium abundances along lines of sight extending out to several hundred parsecs by FUSE and other instruments is making D/H a useful tool for understanding Galactic chemical evolution. We find that…

天体物理学 · 物理学 2007-05-23 Jeffrey L. Linsky

We quantify the gas-phase abundance of deuterium and fractional contribution of stellar mass loss to the gas in cosmological zoom-in simulations from the Feedback In Realistic Environments project. At low metallicity, our simulations…

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…

天体物理学 · 物理学 2008-02-03 Craig J. Hogan

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…

天体物理学 · 物理学 2009-10-30 J. K. Webb , R. F. Carswell , K. M. Lanzetta , R. Ferlet , M. Lemoine , A. Vidal-Madjar , D. V. Bowen

Chemical features of the local stellar disk have firmly established that long-term, continuous star formation has been accompanied by a steady rate of accretion of low-metallicity gas from the halo. We now argue that the recent discovery of…

星系天体物理 · 物理学 2015-05-19 T. Tsujimoto

As the Galaxy evolves, the abundance of deuterium in the interstellar medium (ISM) decreases from its primordial value: deuterium is "astrated". The deuterium astration factor, f_D, the ratio of the primordial D abundance (the D to H ratio…

星系天体物理 · 物理学 2015-05-14 Tijana Prodanovic , Gary Steigman , Brian D. Fields

The theory of Big Bang nucleosynthesis, coupled with an estimate of the primordial deuterium abundance (D/H)_pr, offers insights into the baryon density of the Universe. Independently, the baryon density can be constrained during a…

宇宙学与河外天体物理 · 物理学 2024-01-24 P. A. Kislitsyn , S. A. Balashev , M. T. Murphy , C. Ledoux , P. Noterdaeme , A. V. Ivanchik

The primordial deuterium abundance probes fundamental physics during the Big Bang Nucleosynthesis and can be used to infer cosmological parameters. Observationally, the abundance can be measured using absorbing clouds along the lines of…

宇宙学与河外天体物理 · 物理学 2017-05-03 S. Riemer-Sørensen , S. Kotuš , J. K. Webb , K. Ali , V. Dumont , M. T. Murphy , R. F. Carswell

A new observation of D in a primordial gas cloud, made using the high resolution spectrograph at the Keck telescope, indicates an abundance $ D/H =(1.9-2.5) \times 10^{-4}$ \cite{SCHR}. Since deuterium is destroyed by stars, and the…

天体物理学 · 物理学 2009-10-22 Lawrence M. Krauss , Peter J. Kernan

An accurate value of the deuterium/hydrogen (D/H) ratio in the local interstellar medium (LISM) and a better understanding of the D/H variations with position in the Galactic disk can provide essential information on the primordial D/H…

天体物理学 · 物理学 2009-11-16 Jeffrey L. Linsky

Context: In cold and dense gas prior to the formation of young stellar objects, heavy molecular species (including CO) are accreted onto dust grains. Under these conditions H$_3^+$ and its deuterated isotopologues become more abundant,…

星系天体物理 · 物理学 2019-01-16 A. Giannetti , S. Bovino , P. Caselli , S. Leurini , D. R. G. Schleicher , B. Koertgen , K. M. Menten , T. Pillai , F. Wyrowski

Galactic destruction of primordial deuterium is inevitably linked through star formation to the chemical evolution of the Galaxy. The relatively high present gas content and low metallicity suggest only modest D-destruction. In concert with…

天体物理学 · 物理学 2009-10-30 Monica Tosi , Gary Steigman , Francesca Matteucci , Cristina Chiappini
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