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arXiv · 1902.08191

FLAG Review 2019

S. Aoki·Y. Aoki·D. Becirevic·T. Blum·G. Colangelo·S. Collins·M. Della Morte·P. Dimopoulos·S. Dürr·H. Fukaya·M. Golterman·Steven Gottlieb·R. Gupta·S. Hashimoto·U. M. Heller·G. Herdoiza·R. Horsley·A. Jüttner·T. Kaneko·C. -J. D. Lin·E. Lunghi·R. Mawhinney·A. Nicholson·T. Onogi·C. Pena·A. Portelli·A. Ramos·S. R. Sharpe·J. N. Simone·S. Simula·R. Sommer·R. Van De Water·A. Vladikas·U. Wenger·H. Wittig
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Abstract

We review lattice results related to pion, kaon, $D$-meson, $B$-meson, and nucleon physics with the aim of making them easily accessible to the nuclear and particle physics communities. More specifically, we report on the determination of the light-quark masses, the form factor $f_+(0)$ arising in the semileptonic $K \to \pi$ transition at zero momentum transfer, as well as the decay constant ratio $f_K/f_\pi$ and its consequences for the CKM matrix elements $V_{us}$ and $V_{ud}$. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of $SU(2)_L\times SU(2)_R$ and $SU(3)_L\times SU(3)_R$ Chiral Perturbation Theory. We review the determination of the $B_K$ parameter of neutral kaon mixing as well as the additional four $B$ parameters that arise in theories of physics beyond the Standard Model. For the heavy-quark sector, we provide results for $m_c$ and $m_b$ as well as those for $D$- and $B$-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. We review the status of lattice determinations of the strong coupling constant $\alpha_s$. Finally, in this review we have added a new section reviewing results for nucleon matrix elements of the axial, scalar and tensor bilinears, both isovector and flavor diagonal.

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S. Aoki, Y. Aoki, D. Becirevic, T. Blum, G. Colangelo, S. Collins, M. Della Morte, P. Dimopoulos, S. Dürr, H. Fukaya, M. Golterman, Steven Gottlieb, R. Gupta, S. Hashimoto, U. M. Heller, G. Herdoiza, R. Horsley, A. Jüttner, T. Kaneko, C. -J. D. Lin, E. Lunghi, R. Mawhinney, A. Nicholson, T. Onogi, C. Pena, A. Portelli, A. Ramos, S. R. Sharpe, J. N. Simone, S. Simula, R. Sommer, R. Van De Water, A. Vladikas, U. Wenger, H. Wittig. 2019-02-20. FLAG Review 2019. https://doi.org/10.1140/epjc/s10052-019-7354-7

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