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京大霊長類研の教授ら4人 5億円余を不正支出 大学が報告書 (NHK)

サルの研究で世界的に有名な京都大学霊長類研究所の教授ら4人が、研究費5億円余りを不正に支出していたとする調査報告書を京都大学がまとめたことが分かりました。 研究...

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Extraction of form Factors from a Four-Dimensional Angular Analysis of B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}.

著者 Lees JP , Poireau V , Tisserand V , Grauges E , Palano A , Eigen G , Brown DN , Kolomensky YG , Fritsch M , Koch H , Schroeder T , Hearty C , Mattison TS , McKenna JA , So RY , Blinov VE , Buzykaev AR , Druzhinin VP , Golubev VB , Kozyrev EA , Kravchenko
Phys Rev Lett.2019 Aug 30 ; 123(9):091801.
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An angular analysis of the decay B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ}, ℓ∈{e,μ}, is reported using the full e^{+}e^{-} collision data set collected by the BABAR experiment at the ϒ(4S) resonance. One B meson from the ϒ(4S)→BB[over ¯] decay is fully reconstructed in a hadronic decay mode, which constrains the kinematics and provides a determination of the neutrino momentum vector. The kinematics of the semileptonic decay is described by the dilepton mass squared, q^{2}, and three angles. The first unbinned fit to the full four-dimensional decay rate in the standard model is performed in the so-called Boyd-Grinstein-Lebed approach, which employs a generic q^{2} parametrization of the underlying form factors based on crossing symmetry, analyticity, and QCD dispersion relations for the amplitudes. A fit using the more model-dependent Caprini-Lellouch-Neubert (CLN) approach is performed as well. Our form factor shapes show deviations from previous fits based on the CLN parametrization. The latest form factors also provide an updated prediction for the branching fraction ratio R(D^{*})≡B(B[over ¯]→D^{*}τ^{-}ν[over ¯]_{τ})/B(B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ})=0.253±0.005. Finally, using the well-measured branching fraction for the B[over ¯]→D^{*}ℓ^{-}ν[over ¯]_{ℓ} decay, a value of |V_{cb}|=(38.36±0.90)×10^{-3} is obtained that is consistent with the current world average for exclusive B[over ¯]→D^{(*)}ℓ^{-}ν[over ¯]_{ℓ} decays and remains in tension with the determination from inclusive semileptonic B decays to final states with charm.
PMID: 31524470 [PubMed - in process]
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