相关论文: Lepton Universality Tests with Kaons
High precision electroweak tests, such as deviations from the Standard Model expectations of the Lepton Flavor Universality breaking in K->lnu (with l= e or mu), represent a powerful tool to test the Standard Model and, hence, to constrain…
Available data on measured observables allow deriving estimates for some of the phenomenological parameters that characterize the time-evolution and decay of the neutral kaon system based on the hypothesis of complete positivity. The…
Searches for lepton flavour and lepton number violation in kaon decays by the NA48/2 and NA62 experiments at CERN are presented. A new measurement of the helicity suppressed ratio of charged kaon leptonic decay rates $RK=BR(Ke2)/BR(Kmu2) to…
Several hundred million tau decays have been studied with the BaBar detector at the PEP-II e+e- collider at the SLAC National Accelerator Laboratory. Recent results on Charged Current Lepton Universality and two independent measurements of…
Investigation at a $\phi$--factory can shed light on several debated issues in particle physics. We discuss: i) recent theoretical development and experimental progress in kaon physics relevant for the Standard Model tests in the flavor…
Lepton flavor universality in the Standard Model and hints of its violation in neutral ($R_K$) and charged currents $(R_{D^{(*)}})$ in $B$ decays are presented. We discuss model independent features as well as several leptoquark scenarios…
Motivated by recent experimental measurements on flavour physics, in tension with Standard Model predictions, we perform an updated analysis of New Physics violating Lepton Flavour Universality, by using the effective Lagrangian approach…
In the Standard Model, lepton universality refers to the identical electroweak gauge interactions among charged leptons. The measurement of the branching ratio $R_{e / \mu} = \frac{\Gamma(\pi\rightarrow\ e…
This paper presents the analysis of leptonic and semileptonic kaon decays data done by the FlaviaNet Kaon Working group. Data include all recent results by BNL-E865, KLOE, KTeV, ISTRA+, and NA48. Experimental results are critically reviewed…
I review the current status of nonleptonic kaon decays, placing special emphasis on the recent theoretical progress. In particular, I concentrate on 3 points: (i) the improved determination of \epsilon_K, including both perturbative and…
In the light of the recent LHC data, we study precision tests sensitive to the violation of lepton universality, in particular the violation of unitarity in neutrino mixing. Keeping all data we find no satisfatory fit, even allowing for…
The Large Hadron Collider can do precision physics at a level that is competitive with electroweak precision constraints when probing physics beyond the Standard Model. We present a simple yet general parameterization of the effect of an…
Tests of lepton flavour universality in charged-current $B$ decays offer an excellent opportunity to test the Standard Model, and show hints of new physics in analyses performed by the LHCb, Belle and BaBar experiments. These proceedings…
Rare decays of b-hadrons provide high sensitivity to New Physics effects. Several deviations with respect to the Standard Model predictions have been observed in recent years, leading to significant tensions in global fit analyses. It is…
The NA62 experiment at CERN collected a large sample of K+ --> enu decays during a dedicated run in 2007, aiming at a precise test of lepton universality by measurement of the helicity suppressed ratio RK = BR(K+ --> enu)/BR(K+ --> munu). A…
Searches for violation of lepton flavour universality and lepton number conservation in kaon decays by the NA62 and NA48/2 experiments at CERN, status and future plans of the CERN kaon programme are presented. A precision measurement of the…
During the last few years, new experimental and theoretical results have allowed ever-more-stringent tests of the Standard Model to be performed using kaon decays. This overview of recent progress includes updated results for the evaluation…
Muon-electron universality is tested in $B^0 \to K^{*0} \ \ell^+ \ell^-$ decays, in the dilepton-invariant-mass region above the $\psi(2S)$ resonance. The analysis uses beauty mesons produced in proton-proton collisions recorded by the LHCb…
We review the radiative corrections to the $\tau \to P (P) \nu_\tau [\gamma]$ decays and their implications for several SM tests: lepton universality, CKM unitarity and non-standard interactions.
Several experimental measurements of $B$ meson decays, in tension with Standard Model predictions, exhibit large sources of Lepton Flavour Universality violation. We perform an analysis of the effects of the global fits to the Wilson…