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Related papers: On the Galactic Evolution of $D$ and $^3He$

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We examine the possibility that Big Bang Nucleosynthesis (BBN) may produce non-trivial amounts of $^6$Li. If a primordial component of this isotope could be observed, it would provide a new fundamental test of Big-Bang cosmology, as well as…

Astrophysics · Physics 2008-11-26 Kenneth M. Nollett , Martin Lemoine , David N. Schramm

Big-bang nucleosynthesis (BBN) describes the production of the lightest nuclides via a dynamic interplay among the four fundamental forces during the first seconds of cosmic time. We briefly overview the essentials of this physics, and…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-13 Richard H. Cyburt , Brian D. Fields , Keith A. Olive , Tsung-Han Yeh

Big Bang Nucleosynthesis provides us with an observational insight into the very early Universe. Since this mechanism of light element synthesis comes out of the standard model of particle cosmology which follows directly from General…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-14 Sai Swagat Mishra , Ameya Kolhatkar , P. K. Sahoo

We study the metallicities and abundance ratios of early-type galaxies in cosmological semi-analytic models (SAMs) within the hierarchical galaxy formation paradigm. To achieve this we implemented a detailed galactic chemical evolution…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Matías Arrigoni , Scott C. Trager , Rachel S. Somerville , Brad K. Gibson

The success of primordial nucleosynthesis as a cornerstone of the hot Big Bang model has been limited by the long-standing lithium problem. Recent work presented a self-consistent perturbative analysis of the effects of variations in…

Cosmology and Nongalactic Astrophysics · Physics 2021-02-10 C. J. A. P. Martins

Initial conditions are set by Big bang nucleosynthesis from which we know that 90 per cent of baryons are dark and have essentially unknown chemical composition. In our own Galaxy, there are many clues from individual stars in different…

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

The predictions of Standard Big Bang Nucleosynthesis are summarized and compared with observations of abundances of helium in HII regions, deuterium in quasar absorbers, deuterium and helium-3 in the Galaxy, and lithium in metal-poor stars.…

Astrophysics · Physics 2007-05-23 Craig J. Hogan

Contrary to a recent claim, the inferred primordial abundances of the light elements are quite consistent with the expectations from standard big bang nucleosynthesis when attention is restricted to direct observations rather than results…

Astrophysics · Physics 2008-11-26 Peter J. Kernan , Subir Sarkar

After a short historical (and highly subjective) introduction to the field, I discuss our current understanding of the origin and evolution of the light nuclides D, He-3, He-4, Li-6, Li-7, Be-9, B-10 and B-11. Despite considerable…

Astrophysics · Physics 2009-11-13 Nikos Prantzos

All stellar evolution models for nucleosynthesis require an initial isotopic abundance set to use as a starting point. Generally, our knowledge of isotopic abundances of stars is fairly incomplete except for the Solar System. We present a…

Solar and Stellar Astrophysics · Physics 2015-06-04 Christopher West , Alexander Heger

In this paper we investigate the primordial nucleosynthesis in $\mathscr{L}=\varepsilon^{2-2\beta}R^\beta+{16\pi}m_P^{-2}\mathscr{L}_m$ gravity, where $\varepsilon$ is a constant balancing the dimension of the field equation, and…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-11 David Wenjie Tian

Recent Wilkinson Microwave Anisotropy Probe (WMAP) measurements have determined the baryon density of the Universe $\Omega_b$ with a precision of about 4%. With $\Omega_b$ tightly constrained, comparisons of Big Bang Nucleosynthesis (BBN)…

Nuclear Experiment · Physics 2007-05-23 D. S. Leonard , H. J. Karwowski , C. R. Brune , B. M. Fisher , E. J. Ludwig

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…

Astrophysics · Physics 2009-10-30 Monica Tosi , Gary Steigman , Francesca Matteucci , Cristina Chiappini

Low-mass stars, ~1-2 solar masses, near the Main Sequence are efficient at producing He-3, which they mix into the convective envelope on the giant branch and should distribute into the Galaxy by way of envelope loss. This process is so…

Astrophysics · Physics 2009-11-11 Peter P Eggleton , David S P Dearborn , John C Lattanzio

Within the first 20 minutes of the evolution of the hot, dense, early Universe, astrophysically interesting abundances of deuterium, helium-3, helium-4, and lithium-7 were synthesized by the cosmic nuclear reactor. The primordial abundances…

Astrophysics · Physics 2007-05-23 Gary Steigman

In the standard Big-Bang nucleosynthesis (BBN) model, the primordial $^7$Li abundance is overestimated by about a factor of 2--3 comparing to the astronomical observations, so called the pending cosmological lithium problem. The…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 S. Q. Hou , J. J. He , S. Kubono , Y. S. Chen

The primordial lithium abundance inferred from observations of metal-poor stars is ~3 times smaller than the theoretical value in standard big bang nucleosynthesis (BBN) model. We assume a simple model including a sterile neutrino nu_H with…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-29 Hiroyuki Ishida , Motohiko Kusakabe , Hiroshi Okada

Observations of stellar CNO isotope ratios indicate the presence of additional mixing processes on the red giant branch. An estimate of the resulting stellar He-3 depletion is made, as a function of stellar mass and metallicity. Based on…

Astrophysics · Physics 2007-05-23 Arnold I. Boothroyd , Robert A. Malaney

Big bang nucleosynthesis in a modified gravity model of $f(R)\propto R^n$ is investigated. The only free parameter of the model is a power-law index $n$. We find cosmological solutions in a parameter region of $1< n \leq (4+\sqrt{6})/5$. We…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-21 Motohiko Kusakabe , Seoktae Koh , K. S. Kim , Myung-Ki Cheoun

Big Bang Nucleosynthesis (BBN) explores the first few minutes of nuclei formation after the Big Bang. We present updates that result in new constraints at the 2{\sigma} level for the abundances of the four primary light nuclides -…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-20 Michael Foley , Nishanth Sasankan , Motohiko Kusakabe , Grant. J. Mathews