Related papers: Emerging patterns of New Physics with and without …
We study the implications of the observed excess in $B^+ \to K^+ \nu \bar{\nu}$ under the assumption of Rank-One Flavour Violation, i.e. that New Physics couples to a single specific direction in flavour space. By varying this direction we…
We propose a novel strategy to test lepton flavor universality (LFU) in top decays, applicable to top pair production at colliders. Our proposal exploits information in kinematic distributions and mostly hinges on data-driven techniques,…
At Moriond 2019, Belle collaboration has announced new measurements on the flavour ratios $R_D - R_{D^*}$ which are consistent with their Standard Model predictions within $1.2\sigma$. After inclusion of these measurements, the global…
We investigate new-physics contributions to $b\to s \ell\ell$ transitions in the context of an effective field theory extension of the Standard Model, including operator mixing at one loop. We identify the few scenarios where a single…
The electroweak penguin B decays mediated by $b \to s \ell^+ \ell^- $ transitions are flavour-changing neutral current processes, and are thus sensitive to new physics owing to potential contributions of heavy particles in the quantum loop.…
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…
As one of the hypothetical principles in the Standard Model (SM), lepton flavor universality (LFU) should be tested with a precision as high as possible such that the physics violating this principle can be fully examined. The run of $Z$…
The recent updated angular analysis of the $B\to K^*\mu^+\mu^-$ decay by the LHCb collaboration is interpreted by performing a global fit to all relevant measurements probing the flavour-changing neutral current $b\to s\mu^+\mu^-$…
We analyze the lepton flavor universality violation (LFV) in process $b\to s \ell^+\ell^-$ in an R-parity violating supersymmetric (RPV-SUSY) scenario. The most recent update on $\rk$ from the LHCb collaboration suggests approximately…
The R_K measurement by LHCb suggests non-standard lepton non-universality (LNU) to occur in b -> s l+ l- transitions, with effects in muons rather than electrons. A number of other measurements of b -> s l+ l- transitions by LHCb and…
We extend the Standard Model with the general effective Hamiltonian for the quark level transition $c \to s \ell \nu$ with a complete set of four fermion operators including right-handed neutrinos. The current experimental measurements in…
In the last few years, the ratios $R_{D^{(*)}}$ and of $R_{K^{(*)}}$ have reportedly exhibited significant deviations from the relevant Standard Model predictions, hinting towards a possible violation of Lepton Flavor Universality and a…
Present measurements of b->c tau nu and b->u tau nu transitions differ from the standard model predictions of lepton flavor universality by almost 4sigma. We examine new physics interpretations of this anomaly. An effective field theory…
We perform a global analysis of the bounds from charged lepton flavour violating observables to new physics. We parametrize generic new physics through the Effective Field Theory formalism and perform global fits beyond the common…
The experimental values of the lepton-flavour-universality tests ${\cal R}(D)$ and ${\cal R}(D^*)$ show a tension of about $3.1\sigma$ with their Standard Model prediction. Motivated by this tension, we perform a fit of the $b\to c\tau\nu$…
We revisit the status of the new-physics interpretations of the anomalies in semileptonic $B$ decays in light of the new data reported by Belle on the lepton-universality ratios $R_{D^{(*)}}$ using the semileptonic tag and on the…
The LHCb experiment at the Large Hadron Collider specialises in high-precision measurements of flavour physics with hadrons containing $b$ and $c$ quarks. Lepton flavour universality tests provide an accurate and clear approach to…
Recent results from the LHCb experiment have confirmed that lepton flavor universality is upheld in flavor-changing neutral current processes, such as $B \to K^{(*)} l^+ l^-$. However, discrepancies remain in the charged current sector,…
Over the last few years LHCb with present energies found some discrepancies in $b\to s\ell^+\ell^-$ FCNC transitions including anomalies in the angular observables of $B\to K^*\mu^+\mu^-$, particularly in $P_5^\prime$, in low dimuon mass…
While the LHC has not directly observed any new particle so far, experimental results from LHCb, BELLE and BABAR point towards the violation of lepton flavour universality in $b\to s\ell^{+}\ell^{-}$ and $b\to c\ell\nu$. In this context,…