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Related papers: New BBN limits on Physics Beyond the Standard Mode…

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The simplest, `standard' model of Big Bang Nucleosynthesis (SBBN) assumes three light neutrinos (N_nu = 3) and no significant electron neutrino asymmetry, leaving only one adjustable parameter: the baryon to photon ratio eta. The primordial…

Astrophysics · Physics 2009-11-10 James P. Kneller , Gary Steigman

We review the present status of Higgs physics within the standard model and its extensions. First, we briefly summarize the current experimental exclusion limits from the direct searches with LEP1 and the Tevatron, and assess the discovery…

High Energy Physics - Phenomenology · Physics 2007-05-23 Bernd A. Kniehl

We consider heavy sterile neutrinos $\nu_s$, with mass in the range 10 MeV $\lesssim m_s \lesssim m_{\pi} \sim 135$ MeV, thermally produced in the early universe and freezing out after the QCD phase transition. The existence of these…

High Energy Physics - Phenomenology · Physics 2022-02-24 L. Mastrototaro

We reexamine big bang nucleosynthesis with large-scale baryon density inhomogeneities when the length scale of the density fluctuations exceeds the neutron diffusion length ($\sim 10^7-10^8$ cm at BBN), and the amplitude of the fluctuations…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-12 John D. Barrow , Robert J. Scherrer

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

Comparing the latest observed abundances of 4He and D, we make a ?2 analysis to see whether it is possible to reconcile primordial nucleosynthesis using up-to-date nuclear data of NACRE II and the mean-life of neutrons. If we adopt the…

Cosmology and Nongalactic Astrophysics · Physics 2014-08-05 R. Ichimasa , R. Nakamura , M. Hashimoto , K. Arai

We present a new determination of the primordial helium mass fraction Yp, based on 93 spectra of 86 low-metallicity extragalactic HII regions, and taking into account the latest developments concerning systematic effects. These include…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Y. I. Izotov , T. X. Thuan

The products of primordial nucleosynthesis and the cosmic microwave background (CMB) photons are relics from the early evolution of the Universe whose observations probe the standard model of cosmology and provide windows on new physics…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Gary Steigman

Big bang nucleosynthesis (BBN) is affected by the energy density of a primordial magnetic field (PMF). For an easy derivation of constraints on models for PMF generations, we assume a PMF with a power law (PL) distribution in wave number…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-14 Dai G. Yamazaki , Motohiko Kusakabe

We investigate the observational constraints on the inhomogeneous big-bang nucleosynthesis that Matsuura et al. suggested the possibility of the heavy element production beyond ${}^7$Li in the early universe. From the observational…

Cosmology and Nongalactic Astrophysics · Physics 2013-10-21 Riou Nakamura , Masa-aki Mashimoto , Shin-ichiro Fujimoto , Katsuhiko Sato

Recent observations by Bania et al. (2002) measure He3 versus oxygen in Galactic HII regions, finding that He3/H is within a factor of 2 of the solar abundance for [O/H] > -0.6. These results are consistent with a flat behavior in this…

Astrophysics · Physics 2009-09-15 Elisabeth Vangioni-Flam , Keith A. Olive , Brian D. Fields , Michel Casse

Late-decaying particles naturally arise in many extensions of the Standard Model, directly impacting key cosmological processes in the early universe, such as Big Bang Nucleosynthesis (BBN). BBN studies often consider electromagnetic energy…

High Energy Physics - Phenomenology · Physics 2025-01-17 Lucia Angel , Giorgio Arcadi , Matheus M. A. Paixão , Farinaldo S. Queiroz

We initiate the study of a new class of beyond the Standard Model states that we call "Loryons." They have the defining characteristic of being non-decoupling, in the sense that their physical mass is dominated by a contribution from the…

High Energy Physics - Phenomenology · Physics 2022-02-23 Ian Banta , Timothy Cohen , Nathaniel Craig , Xiaochuan Lu , Dave Sutherland

Provided that matter-antimatter domains are present at the onset of big bang nucleosynthesis (BBN), the number of allowed additional relativistic species increases, compared to the standard scenario when matter-antimatter domains are…

Astrophysics · Physics 2009-11-07 Massimo Giovannini , Elina Keihanen , Hannu Kurki-Suonio

We present the results of a search for a hidden mirror sector in positronium decays with a sensitivity comparable with the bounds set by the prediction of the primordial He$^{4}$ abundance from Big Bang Nucleosynthesis. No excess of events…

Atomic Physics · Physics 2020-03-18 C. Vigo , L. Gerchow , B. Radics , M. Raaijmakers , A. Rubbia , P. Crivelli

One of the three testaments in favor of the big bang theory is the prediction of the primordial elemental abundances in the big-bang nucleosynthesis (BBN). The Standard BBN is a parameter-free theory due to the precise knowledge of the…

Nuclear Theory · Physics 2024-05-28 Vinay Singh , Debasis Bhowmick , D. N. Basu

We present near-infrared spectroscopic observations of the high-intensity HeI 10830 emission line in 45 low-metallicity HII regions. We combined these NIR data with spectroscopic data in the optical range to derive the primordial He…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-03 Y. I. Izotov , T. X. Thuan , N. G. Guseva

The determination of the primeval deuterium abundance has opened a precision era in big-bang nucleosynthesis (BBN), making accurate predictions more important than ever before. We present in analytic form new, more precise predictions for…

Astrophysics · Physics 2009-10-31 Scott Burles , Kenneth M. Nollett , Michael S. Turner

In this work, we revise and update model-independent constraints from Big Bang Nucleosynthesis on MeV-scale particles $\phi$ which decay into photons and/or electron-positron pairs. We use the latest determinations of primordial abundances…

High Energy Physics - Phenomenology · Physics 2021-05-19 Paul Frederik Depta , Marco Hufnagel , Kai Schmidt-Hoberg

We extend a recently developed Big Bang Nucleosynthesis (BBN) code, {\tt PRyMordial}, to constrain a broad class of Grand Unified Theories to which BBN is sensitive, since these lead to varying fundamental couplings. A previously developed…

High Energy Physics - Phenomenology · Physics 2026-04-07 I. M. Dreyer , C. J. A. P. Martins
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