Related papers: $B \to X_s \mu^+ \mu^-$ in Technicolor with Scalar…
Precision tests of the Standard Model and searches for New Physics in the quark flavor sector depend on accurate theoretical calculations of decay rates and spectra for rare, flavor-changing processes. The theoretical status and recent…
The experimental data on $b\to c\tau\bar\nu_\tau$ and $b\to s\ell^+\ell^-$ transitions exhibit sizeable discrepancies with the Standard Model expectations. We present an overview of the present status and discuss possible interpretations…
We report the results of a search for the flavor-changing neutral current process b --> d gamma using a sample of 275 million B meson pairs accumulated by the Belle detector at KEKB. We find no significant signal for the exclusive decays B-…
After an introduction on the peculiarities of flavor-physics measurements at a hadron collider, and on the upgraded Collider Detector at Fermilab (CDF II), I show recent results on two-body B0 and B0s decays into charged, pseudo-scalar,…
In this work we study the flavor changing neutral current(FCNC) decays of the top quark, $t\to c\gamma$ and $t\to c g$. The Standard Model, predictions for the branching ratios of these decays are about $\sim 5\times 10^{-14}$, and $\sim…
We report a search for the flavor-changing neutral current decay $B \to X_{s} \ell^{+} \ell^{-}$ using a 29.5 fb$^{-1}$ data sample accumulated at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB $e^{+}e^{-}$ storage ring.…
Rare flavour-changing neutral-current transitions of the type $s \to d \ell^+\ell^-(\nu\bar\nu)$ and $b \to s \ell^+\ell^-(\nu\bar\nu)$ are analysed in supersymmetric extensions of the Standard Model with generic flavour couplings. It is…
This letter presents a search for the rare flavor-changing neutral current process $B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}$ using data taken with the Belle detector at the KEKB asymmetric energy $e^{+}e^{-}$ collider. The analysis is…
We review the theory and experimental measurements in the flavour changing neutral current (FCNC) processes involving B decays in the context of the standard model (SM). The role of these processes in determining the weak mixing matrix…
We describe the phenomenology of the flavour changing neutral current sector of a supersymmetric model, invariant under the T' discrete flavour group. This model has been proposed in Ref.[1] and describes realistic leptonic and hadronic…
We search for the rare flavor-changing neutral current process $B^- \to \Lambda {\overline p} \nu{\overline{\nu}}$ using data from the BABAR experiment. A total of 424 fb$^{-1}$ of $e^+e^-$ collision data collected at the center-of-mass…
We report a sensitive study of $D_s^+ \to \tau^+ \nu_{\tau}$ decay via $\tau^+ \to e^+ \nu_e \bar{\nu}_{\tau}$ with an integrated luminosity of 1 ab$^{-1}$ at the center-of-mass energy of $4.009$ GeV at a future Super Tau Charm Facility…
We analyse top quark flavor violating decays into a charm quark and a gluon, photon or Z boson in a supersymmetric model incorporating left-right symmetry. We include loop calculations involving contributions from scalar quarks, gluinos,…
Searches for flavor changing neutral currents in top production and decay using data collected by the Compact Muon Solenoid (CMS) experiment at $\sqrt{s}$ = 7 and 8 TeV are presented, corresponding to an integrated luminosity of around 5…
The observation of $B \to \tau \bar{\mu} + \mu \bar{\tau} $ at present experiments would be a clear sign of new physics. In this paper we calculate this process in a 2HDM framework where the decay is mediated by the exchange of spin zero…
Decays of the kind $B^0_{s,d}\to\ell^+\ell^-$ belong to the most favourable processes for probing the flavour structure of the Standard Model, with outstanding sensitivity to new (pseudo)-scalar contributions. While the branching ratio of…
A plethora of ultraviolet completions of the Standard Model have extra U(1) gauge symmetries. In general, the associated massive $Z^\prime$ gauge boson can mediate flavor-changing neutral current processes at tree level. We consider a…
The branching ratio of the rare decay B->X_s gamma provides potentially strong constraints on models beyond the Standard Model. Considering a general scenario with new heavy neutral gauge bosons, present in particular in Z' and gauge…
We discuss the implications of $b \to s \ell^+\ell^-$ measurements and their deviations with respect to the Standard Model predictions in a model-independent framework. We highlight in particular the impact of the recent updated…
We search for b to s\mu^+\mu^- transitions in B meson (B^+, B^0, or B^0_s) decays with 924pb^{-1} of p pbar collisions at sqrt(s)=1.96 TeV collected with the CDF II detector at the Fermilab Tevatron. We find excesses with significances of…