Related papers: New physics searches in $B \rightarrow D^{(*)}\tau…
Semileptonic $B$ meson decays into the four lightest excited charmed meson states ($D_0^*$, $D_1^*$, $D_1$, and $D_2^*$) and their counterparts with $s$ quarks are investigated, including the full lepton mass dependence. We derive the…
LHCb found hints for physics beyond the Standard Model (SM) in $B\to K^*\mu^+\mu^-$, $R(K)$ and $B_s\to\phi\mu^+\mu^-$. These intriguing hints for NP have recently been confirmed by the LHCb measurement of $R(K^*)$ giving a combined…
Using a full BABAR data sample of 426 $fb^{-1}$, we present improved measurements of the ratio ${\cal{R}}(D^{(*)}) = {\cal{B}} (\bar{B} \to D^{(*)}\tau^{-}\bar{\nu}_{\tau})/$ ${\cal{B}} (\bar{B} \to D^{(*)}\ell_{\ell}^{-}\bar{\nu}_{\ell})$,…
We derive the four-fold angular distribution for the semileptonic decay $\bar{B}\to D_2^*(\to D \pi)\,\ell \bar{\nu}$ where $D_2^*$(2460) is a tensor meson. We start with the most general beyond the Standard Model (SM) dimension-six…
The pure leptonic or semileptonic character of tau decays makes them a good laboratory to test the structure of the weak currents and the universality of their couplings to the gauge bosons. The hadronic tau decay modes constitute an ideal…
Inspired by the recently observed tensions between the experimental data and the theoretical predictions, based on QCD factorisation, for several colour-allowed non-leptonic $B$-meson decays, we study the potential size of new physics (NP)…
The rare decay $B^0_s \to \mu^+\mu^-$ plays a key role for the testing of the Standard Model. It is pointed out that the sizable decay width difference $\Delta\Gamma_s$ of the $B_s$-meson system affects this channel in a subtle way. As a…
The observation of anomalies in the charged current $b\rightarrow c\bar{\ell}\nu_{\ell}$ transitions hints the possibility of the existence of new physics beyond the standard model. Inspired by the work done in the beauty quark sector, we…
Semileptonic and leptonic B decays are analyzed in the framework of the relativistic quark model. Special attention is payed to the decays involving $\tau$ lepton. It is found that the calculated particular decay branching fractions are…
We study the longitudinal, transverse, and normal polarization components of the tau lepton in the decays $\bar{B}^0 \to D^{(\ast)} \tau^- \bar\nu_{\tau}$ and discuss their role in searching for new physics (NP) beyond the standard model…
The di-leptons and di-neutrinos observed in the final states of flavor-changing neutral b decays provide an ideal platform for probing physics beyond the standard model. Although the latest measurements of $R_{K^{(*)}}$ agree well with the…
The search for New Physics (NP) beyond the Standard Model (SM) has been a central focus of particle physics, including in the context of $B$-meson decays involving $b \to s \ell \ell$ transitions. These transitions, mediated by…
In a recent paper we studied the effect of new-physics operators with different Lorentz structures on the semileptonic $\Lambda_b \to \Lambda_c \tau \bar{\nu}_{\tau}$ decay. This decay is of interest in light of the $R({D^{(*)}})$ puzzle in…
Discrepancies have been noted between experimental measurements and Standard Model predictions for various observables related to the $B\to(K, K^*,\phi) ll$ processes. Recently, the Belle-II Collaboration observed a $2.8\sigma$ deviation…
The B_s to mu+ mu- decay plays an outstanding role in tests of the Standard Model and physics beyond it. The LHCb collaboration has recently reported the first evidence for this decay at the 3.5 sigma level, with a branching ratio in the…
While the LHC did not observe direct evidence for physics beyond the standard model, indirect hints for new physics were uncovered in the flavour sector in the decays $B\to K^*\mu^+\mu^-$, $B\to K\mu^+\mu^-/B\to Ke^+e^-$,…
The tau neutrino is probably the least studied particle in the SM, with only a handful of interaction events being identified so far. This can in part be attributed to their small production rate in the SM, which occurs mainly through D_s…
Precise measurement of the Electric Dipole Moment (EDM) and anomalous magnetic moment ($g$-2) of particles are important tests of Beyond Standard Model (BSM) physics. It is generally believed that the tau lepton couples more strongly to BSM…
When looking for heavy ($\mathcal{O}$(few TeV)) New Physics, the most efficient way to benefit from both high and low-energy measurements simultaneously is the use of the Standard Model Effective Field Theory (SMEFT). In this talk I…
In this article we investigate the correlations between tauonic $B$ meson decays (e.g. $B\to \tau\nu$, $B\to D^{(*)}\tau\nu$, $B\to \pi\tau\nu$) and electric dipole moments (EDMs), in particular the one of the neutron, in the context of the…