相关论文: A New Light Particle in B Decays?
Motivated by the recent LHCb announcement of a $3.1\sigma$ violation of lepton-flavor universality in the ratio $R_K=\Gamma(B\to K\mu^+\mu^-)/\Gamma(B\to K e^+ e^-)$, we present an updated, comprehensive analysis of the flavor anomalies…
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…
We review recent results from the BABAR and Belle experiments on rare electroweak B-meson decays, with emphasis on those occurring through flavor changing neutral current interactions of the type b -> s l l. The recent results include…
In view of recent experimental indications of violations of Lepton Flavor Universality (LFU) in $B$ decays, we analyze constraints and implications of LFU interactions, both using an effective theory approach, and an explicit dynamical…
We have investigated $B \to (K,K^*)(l\bar l,\nu\bar\nu)$ decay channels and predicted some form factor dependent observables (e.g. branching ratio, forward-backward asymmetry and lepton polarization asymmetry) considering new physics…
In this talk, I review the status and prospects of several low energy flavor observables that are highly sensitive to New Physics effects. In particular I discuss the implications for possible New Physics in b --> s transitions coming from…
Since the discovery of neutrino oscillations it is known that lepton flavour is not conserved. Lepton flavour violating processes in the charged lepton sector have so far however eluded detection; as they are heavily suppressed in the…
Recent anomalies in $B\to K^{(*)}\ell\ell$ meson decays are consistent with exchange of a heavy $Z'$ vector boson. Here we try to connect such new physics to understanding the origin of flavor, by gauging generation number. Phenomenological…
We discuss avenues for diagnosing new physics hinted from lepton nonuniversality in rare $b$-decays, and physics implications.
We explore the flavour structure of custodial Randall-Sundrum (RS) models in the context of the recently observed deviations in the decay of the $B$ mesons. The anomalies in the $b\rightarrow s ll$ processes can be easily fit with partially…
We discuss the status of $b \to s \ell^+\ell^-$ decays in the post-$R_{K^{(*)}}$ era. The recent LHCb update of $R_K$ and $R_{K^*}$ measurements which are now compatible with the Standard Model, constrain new physics contributions to be…
B-anomalies hint towards New Physics violating Lepton Flavor Universality at the TeV scale. The way they manifest points out to very particular structures for this New Physics. In this talk I review some UV-complete models to explain the…
We analyze nonleptonic $B_s$ decays to a charmonium state and a light meson, induced by the $b \to c {\bar c}s$ transition, which are useful to access the $B_s$-${\bar B}_s$ mixing phase $\beta_s$. We use generalized factorization and…
One of the key assumptions of the Standard Model of fundamental particles is that the interactions of the charged leptons, namely electrons, muons, and taus, differ only because of their different masses. While precision tests have not…
In the framework of SU(3) symmetry, we present a general analysis of $B$ meson decays into two lighter uncharmed mesons (both pairs of pseudoscalar mesons and pairs of vector and pseudoscalar mesons). From the analysis we find constraints…
Starting from the general effective hamiltonian relevant to the $b\to s$ transitions, we derive the expressions for the full angular distributions of the $B \to K^{(\ast )} \ell_1 \ell_2$ decay modes, as well as for ${\cal B}(B_s \to…
It was previously shown that unlike the ratios $R_K^{\mu e} \equiv R_K \equiv \Gamma(B \to K \mu^+ \mu^-)/\Gamma(B \to K e^+ e^-)$ and $R_{K^*}^{\mu e} \equiv R_{K^*} \equiv \Gamma(B \to K^* \mu^+ \mu^-)/\Gamma(B \to K^* e^+ e^-)$, the…
The significant divergence between the SM predictions and experimental measurements for the ratios, $R_{D^{(*)}}\equiv \mathcal{B}(\bar{B}\to D^{(*)}\tau^- \bar{\nu}_\tau)/ \mathcal{B}(\bar{B}\to D^{(*)} \ell^{\prime-}…
We discuss the impact of the recent LHCb update on the two lepton-flavour universality ratios $R_K$ and $R_{K^*}$, and the CMS update of $B({B_s \to \mu^+\mu^-})$ regarding the possibility of New Physics in $b\to s\ell^+\ell^-$ decays. We…
We derive the upper bounds on certain products of R-parity- and lepton-flavor-violating couplings from $B \ra X_s {l_i}^+ {l_j}^-$ decays. These modes of B-meson decays can constrain the product combinations of the couplings with one or…