相关论文: Theoretical status of $B \to K^* \mu^+\mu^-$: The …
We analyze the $B\to K_2^*(\to K\pi)l^+l^-$ (with $l=e,\mu,\tau$) decay in the standard model and two new physics scenarios: vector-like quark model and family non-universal $Z'$ model. We derive its differential angular distributions,…
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…
The modern viewpoint is that the Standard Model is the leading part of an effective field theory that obeys the symmetry $SU(3)_C \times SU(2)_L \times U(1)_Y$. Since the discovery of the Higgs boson, it is generally assumed that this…
We study all possible observables in $B\to D^{(\ast)}\tau\nu_{\tau}$ with new physics (NP), including new vector, scalar and tensor interactions, and investigate the prospects of extracting NP Wilson coefficients with optimal observables.…
We present a complete and optimal set of observables for the exclusive 4-body B meson decay B -> K*(->K pi) l+l- in the low dilepton mass region, that contains a maximal number of clean observables. This basis of observables is built in a…
A number of observables related to the $b \to s \ell^+ \ell^-$ transition show deviations from their standard model predictions. A global fit to the current $b\rightarrow s\ell^+\ell^-$ data suggests several new physics solutions.…
We investigate the observables available in the angular distribution of B to K* mu+ mu- to identify those suitable for measurements in the first few years of LHC data taking. As experimental uncertainties will dominate, we focus on…
We report on our studies of $B\to K_Jl^+l^-$ in the standard model and several new physics variations, with $K_J$ denoting a kaonic resoanance. In terms of helicity amplitudes, we derive a compact form for the full angular distributions,…
Transitions of the type $b \to s l^+ l^-$ are flavour changing neutral current processes where new physics can enter in competing loop diagrams with respect to the Standard Model contributions. In these decays several observables sensitive…
Recent LHCb measurements show small discrepancies with respect to the Standard Model (SM) predictions in selected angular distributions of the mode $B^0 \to K^{*0} \mu^+ \mu^-$. The possibility of explaining such tensions within theories…
Recent measurements of the lepton flavor universality ratios $R^{\mu e}_{K}$ and $R^{\mu e}_{K^*}$ in $B\to \left(K, K^*\right)\mu^{+}\mu^{-}\left(e^+e^-\right)$ at LHCb align with the Standard Model predictions, necessitating search for…
In recent years, intriguing hints for the violation of Lepton Flavour Universality (LFU) have been accumulated in semileptonic $B$ decays, both in the neutral-current transitions $b\to s\ell^+\ell^-$ (i.e., $R_K$ and $R_{K^*}$) and the…
Recent experimental data on several observables in semileptonic $B$-meson decays are found to be in tension with the corresponding Standard Model predictions. Most of these deviations are related to $b \to c$ and $b \to s$ flavour changing…
Recently, the LHC has found several anomalies in exclusive semileptonic b --> s l^+ l^- decays. In this proceeding, we summarize the most important results of our global analysis of the relevant decay modes. After a discussion of the…
Disentangling New Physics effects from the Standard Model requires a good understanding of all pieces that stem from the latter, especially the uncertainties that might plague the theoretical estimations within the Standard Model. In the…
Besides being important to determine Standard Model parameters such as the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$, semileptonic $B$ decays seem also promising to reveal new physics (NP) phenomena, in particular in connection with the…
We present, for the first time, the six-fold differential decay density expression for $\Lambda^0_b\to\Lambda^+_{c} l^- \bar{\nu}_{l}$, taking into account the polarisation of the $\Lambda^0_b$ baryon and a complete basis of new physics…
Recently, the LHCb Collaboration provided updated measurements for the lepton flavour ratios $R_K$ and $R_{K^*}$. The currently observed values align with the predictions of the standard model. In light of these recent updates, our…
We revisit the decay $\Lambda_b^0\to \Lambda_c^+ \ell^-\bar\nu$ ($\ell = e,\mu,\tau$) with a subsequent two-body decay $\Lambda_c^+ \to \Lambda^0 \pi^+$ in the Standard Model and in generic New Physics models. The decay's joint…
We provide improved Standard Model theory predictions for the exclusive rare semimuonic processes $B\to K^{(*)}\mu^+\mu^-$ and $B_s\to\phi\mu^+\mu^-$. Our results are based on a novel parametrization of the non-local form factors, which…