The impact of new d(p,γ)3 rates on Big Bang Nucleosynthesis
نویسندگان
چکیده
We consider the effect on Big Bang Nucleosynthesis (BBN) of new measurements $d(p,\gamma){}^3$He cross section by LUNA Collaboration. These have an important primordial abundance D/H which is also sensitive to baryon density at time BBN. re-evaluated thermal rate for this reaction, using a world average data, we describe with model-independent polynomials; our results are in good agreement similar analysis LUNA. then perform full likelihood combining BBN and Planck cosmic microwave background (CMB) chains combined previous compare rates. Concordance between CMB anisotropy spectrum old rates was excellent. The predicted deuterium value $({\rm D/H})_{\rm BBN+CMB}^{\rm old} = (2.57 \pm 0.13) \times 10^{-5}$ can be compared determined from quasar absorption systems obs} (2.55 0.03) 10^{-5} $. Using find BBN+CMB} (2.51 0.11) 10^{-5}$. thus consistency among theory, ${}^4$He observations, CMB, when reaction fit data-driven approach. that data tightens constraints number relativistic degrees freedom during BBN, giving effective light neutrino species $N_\nu 2.880 0.144$ Standard Model particle physics. Finally, note observed continues more precise than BBN+CMB prediction, whose error budget now dominated $d(d,n){}^3$He $d(d,p){}^{3}{\rm H}$.
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ژورنال
عنوان ژورنال: Journal of Cosmology and Astroparticle Physics
سال: 2021
ISSN: ['1475-7516', '1475-7508']
DOI: https://doi.org/10.1088/1475-7516/2021/03/046