相关论文: BR(Bs to mu+ mu-) as an electroweak precision test
LHCb, bolstered up by the 10^12 b-hadrons produced yearly, is an excellent place to study rare B decays. The B_s to mu^+ mu^- decay, generated by flavour-changing neutral current, is strongly suppressed within the Standard Model (SM).…
Measurements of $b \rightarrow s \mu^+ \mu^-$ transitions indicate that there may be a new physics field coupling to di-muon pairs associated with the $b$ to $s$ flavour transition. Including the 2022 LHCb reanalysis of $R_K$ and…
We present results from the global electroweak fit to precision measurements in the Standard Model (SM). The fit uses the latest theoretical calculations for observables on the $Z$ pole and the $W$ boson mass, yielding precise SM…
We study those dimension 6 effective operators which generate flavor-changing quark-gluon transitions of the third generation quarks, with t -> g + u(c) and b -> g + d(s), and which could be of interest for LHC experiments. We analyze the…
We propose a new model with flavor-dependent gauged $U(1)_{B-L_1}\times U(1)_{B-L_{2}-L_{3}}$ symmetry in addition to the flavor-blind one in the standard model. The model contains three right-handed neutrinos to cancel gauge anomalies and…
By bosonization of an extended NJL model we derive an effective meson theory which describes the interplay between chiral symmetry and heavy quark dynamics. This effective theory is worked out in the low-energy regime using the gradient…
In this work we consider the implications of current $b \to s \ell^+ \ell^-$ ($\ell=e,\,\mu$) measurements on several $B \to K^* \tau^+ \tau^-$ observables under the assumption that the possible new physics can have both universal as well…
This contribution illustrates a new search for the flavor-changing neutral-current decay ${B^+ \to K^+ \nu \bar \nu}$ performed by the Belle II experiment at the SuperKEKB asymmetric-energy electron-positron collider. In this study, a…
We analyze the compatibility of the hypothesis of third-family quark-lepton unification at the TeV scale with electroweak precision data, lepton flavor universality tests, and high-$p_T$ constraints. We work within the framework of the UV…
The left-right model is a gauge theory of electroweak interactions based on the gauge symmetry SU(2)_R . The main motivations for this model are that it gives an explanation for the parity violation of weak interactions, provides a…
We study how large the rate of the lepton-flavor violating Higgs decay h->tau mu can be in the (R-parity conserving) MSSM. We make no assumptions, such as universality or alignment, about the flavor structure of the MSSM. We only assume…
Rare $B$ meson decays offer an opportunity to probe a light hidden $Z'$ boson. In this work we explore a new channel $B_q \to \gamma Z'$ ($q = d, s$) followed by a cascade decay of $Z'$ into an invisible (neutrino or dark matter) or charged…
We report the result of a search for the decay $B^{-}\to\mu^{-}\bar\nu_\mu$. The signal events are selected based on the presence of a high momentum muon and the topology of the rest of the event showing properties of a generic $B$-meson…
We investigate the two loop electroweak corrections to B meson rare decays $\bar B\rightarrow X_s\gamma$ and $B_s^0\rightarrow \mu^+\mu^-$ in the minimal supersymmetry standard model (MSSM) extension with two triplets and one singlet…
The flavor-violating decay of a new neutral massive gauge boson $Z^\prime\to\mu e$ is analyzed in the context of extended models, in which this particle emerges. By means of the analysis of the $\mu\to e\gamma$ decay, $\mu-e$ conversion…
We analyze the $\tau^-\to(K\pi)^-\nu_\tau$ decays within an effective field theory description of heavy new physics (NP) modifying the SM left-handed weak charged current and include refined SM input for the participant meson form factors…
Partial compositeness is a key ingredient of models where the electroweak symmetry is broken by a composite Higgs state. Recently, a UV completion of partial compositeness was proposed, featuring a new strongly coupled gauge interaction as…
This talk highlights, from a theoretical point of view, some recent exciting results in flavor physics, as well as future prospects. We discuss possible implications of a subset of the experimental results in tension with the standard…
In the framework of the Standard Model Effective Field Theory, we compare the lower bounds on the scale of new physics possibly contributing to the $f\bar{f}h$ effective couplings, obtained from the measurements of different observables,…
Charged lepton flavor violating processes are forbidden in the standard model (SM), hence the observation of charged lepton flavor transitions would represent a clear signal of new physics beyond the standard Model. In this work, we…