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Major progress has been made in kaon physics in the past 50 years. The number of KL->pi+pi- events has increased by 6 orders of magnitude, and the observed CP violation was experimentally proven to be caused by a complex phase in the CKM…

High Energy Physics - Experiment · Physics 2014-12-19 Taku Yamanaka

In kaon physics, several new precision measurements on flavour variables and CP violation have performed in the recent years. Presented are a new precise determination of the CKM parameter |V_us|, which combines the results of all…

High Energy Physics - Experiment · Physics 2008-07-18 Rainer Wanke

The recent observation of B_d -> pi^0 pi^0 at the B factories with a surprisingly large branching ratio represents a challenge for theory, and complements the amazingly small B_d -> pi^+ pi^- rate. We point out that all puzzling B -> pi pi…

High Energy Physics - Phenomenology · Physics 2009-11-10 Andrzej J. Buras , Robert Fleischer , Stefan Recksiegel , Felix Schwab

The CKM matrix element $|V_{us}|$ can be extracted from the experimental measurement of semileptonic $K\to\pi$ decays. The determination depends on theory input for the corresponding vector form factor in QCD. We present a preliminary…

High Energy Physics - Lattice · Physics 2012-12-14 Peter A. Boyle , Jonathan M. Flynn , Andreas Jüttner , Christopher Sachrajda , Karthee Sivalingam , James M. Zanotti

We reemphasize that the ratio $R_{s\mu} \equiv \overline{\mathcal{B}}(B_s\to\mu\bar\mu)/\Delta M_s$ is a measure of the tension of the Standard Model (SM) with latest measurements of $\overline{\mathcal{B}}(B_s\to\mu\bar\mu)$ that does not…

High Energy Physics - Phenomenology · Physics 2021-11-18 Christoph Bobeth , Andrzej J. Buras

We emphasize the power of correlations between flavour observables in the search for New Physics and identify a number of correlations that could allow to discover New Physics even if it would appear at the level of 20% of the Standard…

High Energy Physics - Phenomenology · Physics 2013-10-01 Andrzej J. Buras

At present, the measurements of some observables in $B \to K^* \mu^+\mu^-$ and $B_s^0 \to \phi \mu^+ \mu^-$ decays, and of $R_{K^{(*)}} \equiv {\cal B}(B \to K^{(*)} \mu^+ \mu^-)/{\cal B}(B \to K^{(*)} e^+ e^-)$, are in disagreement with…

High Energy Physics - Phenomenology · Physics 2019-05-08 Jacky Kumar , David London

Recent experimental results of ${\cal R}(D^{(*)})$ deviate from the standard model (SM) by $3.1\sigma$, suggesting a new physics (NP) that affects the $b\to c \tau \bar\nu_\tau$ transition. Motivated by this, we investigate the possible NP…

High Energy Physics - Phenomenology · Physics 2019-12-18 Xiao-Long Mu , Ying Li , Zhi-Tian Zou , Bin Zhu

A rare decay $K_L \to \mu^+ \mu^- $ has been measured precisely, while a rare decay $K_S \to \mu^+ \mu^- $ will be observed by an upgrade of the LHCb experiment. Although both processes are almost CP-conserving decays, we point out that an…

High Energy Physics - Phenomenology · Physics 2017-11-16 Giancarlo D'Ambrosio , Teppei Kitahara

We perform a study of the new physics effects in semileptonic FCNC processes within a low-energy approximation of the anomaly-free supersymmetic extension of the SM with additional $Z'$ vector field. The key feature of the model is the…

High Energy Physics - Phenomenology · Physics 2023-03-06 A. V. Bednyakov , A. I. Mukhaeva

We extend previous relativistic mean-field (RMF) calculations of multi-$\bar K$ nuclei, using vector boson fields with SU(3) PPV coupling constants and scalar boson fields constrained phenomenologically. For a given core nucleus, the…

Nuclear Theory · Physics 2008-11-26 D. Gazda , E. Friedman , A. Gal , J. Mareš

$|\Delta c|=|\Delta u|=1$ processes are unique probes of flavor physics in the up-sector within and beyond the Standard Model (SM). SM tests with rare semileptonic charm meson decays are based on an approximate CP--symmetry, a superior…

High Energy Physics - Phenomenology · Physics 2021-02-02 Rigo Bause , Marcel Golz , Gudrun Hiller , Andrey Tayduganov

We discuss the observables for the B->K*(->K pi)ll decay, focusing on both CP-averaged and CP-violating observables at large and low hadronic recoil with special emphasis on their low sensitivity to form-factor uncertainties. We identify an…

High Energy Physics - Phenomenology · Physics 2015-06-15 Sebastien Descotes-Genon , Tobias Hurth , Joaquim Matias , Javier Virto

In this paper we revisit, from a different perspective, a long-standing question: ``Is the systematic deficit observed in all branching ratios mediated by a $b\to s \mu\mu$ transition due to New Physics, or to a hypothetical constant…

High Energy Physics - Phenomenology · Physics 2026-05-08 P. Alvarez-Cartelle , B. Capdevila , E. Lunghi , J. Matias

The availability of high intensity kaon beams at the CERN SPS North Area gives rise to unique possibilities for sensitive tests of the Standard Model in the quark flavor sector. Precise measurements of the branching ratios for the…

High Energy Physics - Experiment · Physics 2023-03-22 Matthew Moulson

Measurements of the combined branching ratios for $B^\pm \to \pi^\pm K$ and $B_d \to \pi^\mp K^\pm$ allow interesting constraints on the CKM angle $\gamma$, the ratio $r \equiv |T'|/|P'|$ of the current-current and penguin operator…

High Energy Physics - Phenomenology · Physics 2007-05-23 Robert Fleischer , Thomas Mannel

We construct the New Minimal Standard Model that incorporates the new discoveries of physics beyond the Minimal Standard Model (MSM): Dark Energy, non-baryonic Dark Matter, neutrino masses, as well as baryon asymmetry and cosmic inflation,…

High Energy Physics - Phenomenology · Physics 2009-09-29 Hooman Davoudiasl , Ryuichiro Kitano , Tianjun Li , Hitoshi Murayama

The decays and mixing of $K$ mesons are remarkably sensitive to the weak interactions of quarks and leptons at high energies. They provide important tests of the standard model at both first and second order in the Fermi constant $G_F$ and…

We review the current status and implications of the anomalies (i.e. deviations from the Standard Model predictions) in semi-leptonic $B$ meson decays, both in the charged and in the neutral current. In $b\to s\ell^+\ell^-$ transitions…

High Energy Physics - Phenomenology · Physics 2023-12-25 Bernat Capdevila , Andreas Crivellin , Joaquim Matias

We perform a model independent analysis of new physics in $B^*_s \rightarrow \mu^+ \mu^-$ decay. We intend to identify new physics operator(s) which can provide large enhancement in the branching ratio of $B^*_s \rightarrow \mu^+ \mu^-$…

High Energy Physics - Phenomenology · Physics 2018-02-14 Dinesh Kumar , Jyoti Saini , Shireen Gangal , Sanjeeda Bharati Das