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Related papers: The cosmological 7Li problem from a nuclear physic…

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We have studied the 4He(3He,gamma)7Be, 3He(3He,2p)4He, and 7Be(p,gamma)8B reactions of the solar p-p chain, using microscopic cluster models. Among other results, we showed that the 6Li+p channel has a nontrivial effect on the 7Be-producing…

Nuclear Theory · Physics 2009-11-06 Attila Csoto , Karlheinz Langanke

We examine in detail how BBN theory is constrained, and what predictions it can make, when using only the most model-independent observational constraints. We avoid the uncertainties and model-dependencies that necessarily arise when solar…

Astrophysics · Physics 2009-09-15 Brian D. Fields , Kimmo Kainulainen , Keith A. Olive , David Thomas

Big Bang Nucleosynthesis (BBN) is an important stage of a homogeneous and isotropic expanding universe. The results of calculation of the synthesis of light elements during this epoch can then be compared with the abundances of the light…

Nuclear Theory · Physics 2023-03-15 Chen Wu

Big Bang Nucleosynthesis (BBN) relevance reactions 3He(2H,{\gamma})5Li, 3H(3He,{\gamma})6Li, 5Li(n,{\gamma})6Li as a key to approach for scenario of 6Li formation are treated. The rates of reaction for these processes are analyzed.…

We test different Big Bang Nucleosynthesis scenarios using the recent results on the Cosmic Microwave Background Anisotropies provided by the BOOMERanG and MAXIMA-1 experiments versus the observed abundances of 4He, D and 7Li. The…

Astrophysics · Physics 2009-10-31 S. Esposito , G. Mangano , A. Melchiorri , G. Miele , O. Pisanti

The two-step process of transfer followed by breakup is explored by measuring a rather complete set of exclusive data for reaction channels populating states in the ejectile continua of the $^7$Li+$^{93}$Nb system at energies close to the…

Primordial nucleosynthesis is inevitable during the early evolution of an expanding universe filled with radiation and matter (baryons). However, the precise abundance yields depend sensitively on the baryon density, the radiation content…

Astrophysics · Physics 2007-05-23 Gary Steigman

Angular distributions of 7Li(7Li,t), (7Li,alpha) and (7Li,6He) reactions were measured for laboratory energies from 2 - 16 MeV. Exact finite range DWBA analyses were performed with the aim to identify contributions of direct processes and…

Nuclear Experiment · Physics 2011-09-15 P. Rosenthal , H. Freiesleben , B. Gehrmann , I. Gotzhein , K. W. Potthast , B. Kamys , Z. Rudy

We explore effects of the screening due to the relativistic electron-positron plasma and presence of resonances in the secondary reactions leading to A=7 nuclei during the Big Bang Nucleosynthesis. In particular, we investigate and examine…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-20 Michael A. Famiano , A. Baha Balantekin , Toshitaka Kajino

In this thesis we study the influence of a possible variation of fundamental "constants" on the process of Big Bang Nucleosynthesis (BBN). Our findings are combined with further studies on variations of constants in other physical processes…

High Energy Physics - Phenomenology · Physics 2008-12-18 Steffen Stern

The total cross sections of the radiative proton capture on 8Li at astrophysical energies were considered in the framework of the modified potential cluster model with forbidden states, with the classification of the orbital cluster states…

Nuclear Theory · Physics 2020-07-03 S. B. Dubovichenko , N. A. Burkova , A. V. Dzhazairov-Kakhramanov

Cross sections for production of 6He, 6Li, 7Li, and 7Be in the alpha+alpha reaction were measured at bombarding energies of 159.3, 279.6, and 619.8 MeV, and are found to decrease rapidly with increasing energy. These cross sections are…

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

The persistent discrepancy between observations of 7Li with putative primordial origin and its abundance prediction in Big Bang Nucleosynthesis (BBN) has become a challenge for the standard cosmological and astrophysical picture. We point…

High Energy Physics - Phenomenology · Physics 2010-11-29 Maxim Pospelov , Josef Pradler

Big bang nucleosynthesis (BBN) and the cosmic microwave background (CMB) have a long history together in the standard cosmology. The general concordance between the predicted and observed light element abundances provides a direct probe of…

Astrophysics · Physics 2009-11-10 Richard H. Cyburt

We calculate primordial abundances of light elements produced during big bang nucleosynthesis when the fine structure constant and/or the cosmic expansion rate take non-standard values. We compare them with the recent values of observed D,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Kazuhide Ichikawa , Masahiro Kawasaki

We investigate the possibility that inhomogeneous nucleosynthesis may eventually be used to explain the abundances of \li6, \be9 and B in population II stars. The present work differs from previous studies in that we have used a more…

Primordial nucleosynthesis provides a probe of the Universe during its early evolution. Given the progress exploring the constituents, structure, and recent evolution of the Universe, it is timely to review the status of Big Bang…

Astrophysics · Physics 2009-11-11 Gary Steigman

Recent data resulting from studies of two-nucleon transfer reaction on 11Li, analyzed through a unified nuclear-structure-direct-reaction theory have provided strong direct as well as indirect confirmation, through the population of the…

Nuclear Theory · Physics 2012-12-12 Gregory Potel , Andrea Idini , Francisco Barranco , Enrico Vigezzi , Ricardo A. Broglia

The conventional approach to search for departures from the standard model of physics during Big Bang Nucleosynthesis involves a careful, and subtle measurement of the mass fraction of baryons consisting of helium. Recent measurements of…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-13 Ryan Cooke