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Related papers: Possible solution to the $^7$Li problem by the lon…

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Using the recent WMAP determination of the baryon-to-photon ratio, 10^{10} \eta = 6.14 to within a few percent, big bang nucleosynthesis (BBN) calculations can make relatively accurate predictions of the abundances of the light element…

Astrophysics · Physics 2009-09-15 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

The primordial abundance of 7Li as predicted by Big Bang Nucleosynthesis (BBN) is more than a factor 2 larger than what has been observed in metal-poor halo stars. Herein, we analyze the possibility that this discrepancy originates from…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-24 C. Broggini , L. Canton , G. Fiorentini , F. L. Villante

The abundance of primordial lithium is derived from the observed spectroscopy of metal-poor stars in the galactic halo. However, the observationally inferred abundance remains at about a factor of three below the abundance predicted by…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-30 G. J. Mathews , A. Kedia , N. Sasankan , M. Kusakabe , Y. Luo , T. Kajino , D. G. Yamazaki , T. Makki , M. El Eid

We calculate the relic density of stau at the beginning of the Big-Bang Nucleosynthesis (BBN) era in the coannihilation scenario of minimal supersymmetric standard model (MSSM). In this scenario, stau can be long-lived and form bound states…

High Energy Physics - Phenomenology · Physics 2011-02-02 Toshifumi Jittoh , Kazunori Kohri , Masafumi Koike , Joe Sato , Takashi Shimomura , Masato Yamanaka

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

The role of novae as producers of galactic lithium has been suggested since the 1970s, and it has been reconsidered recently with the detection of $^7$Be in their outbursts. At the same time, stellar models are moving forward to comprehend…

Astrophysics of Galaxies · Physics 2025-11-19 C. T. Nguyen , G. Cescutti , F. Matteucci , F. Rizzuti , A. Mucciarelli , D. Romano , L. Magrini , A. J. Korn , A. Bressan , L. Girardi

The low-scale gauge mediation scenario of supersymmetry breaking predicts very light gravitino, which makes the next lightest supersymmetric particle (NLSP) quasi stable. We study the LHC phenomenology of the case that the NLSP is the stau.…

High Energy Physics - Phenomenology · Physics 2015-06-03 Masaki Asano , Takumi Ito , Shigeki Matsumoto , Takeo Moroi

We consider physics beyond the Standard Model in which a long-lived electromagnetically charged massive particle species (CHAMP) appears. We discuss the unique sensitivity the early Universe exhibits on the mere presence and on the decay of…

High Energy Physics - Phenomenology · Physics 2009-09-21 Josef Pradler

Big Bang nucleosynthesis (BBN) is the earliest sensitive probe of the values of many fundamental particle physics parameters. We have found the leading linear dependences of primordial abundances on all relevant parameters of the standard…

Astrophysics · Physics 2008-11-26 Thomas Dent , Steffen Stern

Thanks to the accurate determination of the baryon density of the universe by the recent cosmic microwave background experiments, updated predictions of the standard model of Big Bang nucleosynthesis now yield the initial abundance of the…

Astrophysics · Physics 2015-06-24 C. Charbonnel , F. Primas

The lithium problem arises from the significant discrepancy between the primordial 7Li abundance as predicted by BBN theory and the WMAP baryon density, and the pre-Galactic lithium abundance inferred from observations of metal-poor…

Astrophysics · Physics 2009-10-16 Richard H. Cyburt , Brian D. Fields , Keith A. Olive

Standard big bang nucleosynthesis (SBBN) has been remarkably successful, and it may well be the correct and sufficient account of what happened. However, interest in variations from the standard picture come from two sources: First, big…

Astrophysics · Physics 2007-05-23 Hannu Kurki-Suonio

We present a parametrized study of the effects of free thermal neutron injection on primordial nucleosynthesis, where both the rate and the time scale of injection are varied. This generic approach is found to yield a successful solution…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Daniel Albornoz Vasquez , Alexander Belikov , Alain Coc , Joseph Silk , Elisabeth Vangioni

The nuclei of the lithium isotopes are fragile, easily destroyed, so that, at variance with most of the other elements, they cannot be formed in stars through steady hydrostatic nucleosynthesis. The 7Li isotope is synthesized during…

Astrophysics of Galaxies · Physics 2015-05-18 Monique Spite , François Spite

The depletion of lithium during the pre-main sequence and main sequence phases of stellar evolution plays a crucial role in the comparison of the predictions of big bang nucleosynthesis with the abundances observed in halo stars. In the…

Astrophysics · Physics 2011-05-05 M. H. Pinsonneault , T. P. Walker , G. Steigman , V. K. Narayanan

A critical review is given of the current status of cosmological nucleosynthesis. In the framework of the Standard Model with 3 types of relativistic neutrinos, the baryon-to-photon ratio, $\eta$, corresponding to the inferred primordial…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-23 Brian D. Fields , Paolo Molaro , Subir Sarkar

The last parameter of big-bang nucleosynthesis, the baryon density, is being pinned down by measurements of the deuterium abundance in high-redshift hydrogen clouds. When it is determined, it will fix the primeval light-element abundances.…

Astrophysics · Physics 2008-11-26 David N. Schramm , Michael S. Turner

We investigate the non-radiative decay during nucleosynthesis of a massive tau neutrino with mass 0.1 - 1 MeV into an electron neutrino and a scalar or pseudoscalar particle, $\phi$. The full Boltzmann equation is used and shown to give…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Hannestad

I review measurements of the most important reactions involved in the creation and destruction of Li and Be during big bang nucleosynthesis (BBN) as well as their uncertainties and the relative contributions they make to the uncertainty in…

Cosmology and Nongalactic Astrophysics · Physics 2020-02-14 Barry Davids

A new evaluation of the constraint on the number of light neutrino species (N_nu) from big bang nucleosynthesis suggests a discrepancy between the predicted light element abundances and those inferred from observations, unless the inferred…

High Energy Physics - Phenomenology · Physics 2009-04-13 N. Hata , R. J. Scherrer , G. Steigman , D. Thomas , T. P. Walker , S. Bludman , P. Langacker
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