Weak radiative decays of the B mesons belong to the most important flavor changing processes that provide constraints on physics at the TeV scale. In the derivation of such constraints, accurate standard model predictions for the inclusive branching ratios play a crucial role. In the current Letter we present an update of these predictions, incorporating all our results for the O(α_{s}^{2}) and lower-order perturbative corrections that have been calculated after 2006. New estimates of nonperturbative effects are taken into account, too. For the CP- and isospin-averaged branching ratios, we find B_{sγ}=(3.36±0.23)×10^{-4} and B_{dγ}=(1.73_{-0.22}^{+0.12})×10^{-5}, for E_{γ}>1.6 GeV. Both results remain in agreement with the current experimental averages. Normalizing their sum to the inclusive semileptonic branching ratio, we obtain R_{γ}≡(B_{sγ}+B_{dγ})/B_{cℓν}=(3.31±0.22)×10^{-3}. A new bound from B_{sγ} on the charged Higgs boson mass in the two-Higgs-doublet-model II reads M_{H^{±}}>480 GeV at 95% C.L.
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http://dx.doi.org/10.1103/PhysRevLett.114.221801 | DOI Listing |
Chem Sci
January 2025
State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry, Jilin University Changchun 130012 China
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January 2025
Department of Chemistry, University of California Irvine, Irvine, CA, USA.
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Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan.
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January 2025
Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, People's Republic of China; University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China. Electronic address:
Diabetes mellitus (DM) is a chronic metabolic disorder characterized by elevated blood glucose levels, generally due to defects of insulin action or secretion. Inhibition of α-glucosidase, an enzyme responsible for carbohydrate degradation, is a promising strategy for managing postprandial hyperglycemia in diabetic patients. In this study, two new C-linked diarylheptanoid dimers, kaemgalanganols A (1) and B (2), were isolated from K.
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