Related papers: B_{s,d}--> mu^+ mu^- in technicolor model with sca…

Branching fraction and effective lifetime measurements of the rare decay $B^0_s\to\mu^+\mu^-$ and searches for the decays $B^0\to\mu^+\mu^-$ and $B^0_s\to\mu^+\mu^-\gamma$ are reported using proton-proton collision data collected with the…

Two of the outstanding discrepancies between weak interaction phenomenology and the standard model come in the large size of the $\Delta I={1\over 2}$ enhancement in $K$ decays and in the small value of the $B$ semileptonic branching ratio.…

We consider the exclusive B_s -> phi mu+ mu- process in the standard model using a constituent quark loop model approach together with a simple parameterization of the quark dynamics. The model allows to compute the decay form factors and…

We perform a model independent analysis to identify new physics operators which can enhance the branching ratio of $B_s^* \rightarrow \mu^+ \mu^-$ above its Standard Model (SM) prediction. We find that none of the new physics operators…

We present the recent BaBar searches for the leptonic decay B+ --> tau+ nu and for the rare decay B --> K(*) nu nubar, using a data sample of about 470 x 10^6 BB pairs. Both searches use a technique in which one B meson is hadronically…

We combine the results of CDF and DO searches for the rare decays B_s to mu+ mu- and B_d to mu+ mu-. The experiments use 364 pb-1 and 300 pb-1 of data respectively. The limits on the branching ratios are obtained by normalizing the…

The rare decay B_s -> mu^+ mu^- provides an important constraint on possible deviations from the Standard Model in b-s-l-l interactions. The present weighted average of its branching ratio measurements amounts to (3.34 \pm 0.27) x 10^-9,…

We perform a model independent analysis of new physics in $B^*_s \rightarrow \mu^+ \mu^-$ decay. We intend to identify new physics operator(s) which can provide large enhancement in the branching ratio of $B^*_s \rightarrow \mu^+ \mu^-$…

A search for the rare decays Bs->mu+mu- and B0->mu+mu- is performed using data collected in 2011 and 2012 with the LHCb experiment at the Large Hadron Collider. The data samples comprise 1.1 fb^-1 of proton-proton collisions at sqrt{s} = 8…

Measurements of Flavor Changing Neutral Current (FCNC) processes (rare decays, flavor mixing) play a key role to pursue new physics beyond the Standard Model. We present recent analysis results about some FCNC transitions performed by CDF…

It is well known that the Minimal Supersymmetric Standard Model (MSSM) can enhance Br[B_{d,s}->mu^+ mu^-] by orders of magnitude, even if we assume the Cabibbo-Kobayashi-Maskawa (CKM) matrix to be the only source of flavour violation. Of…

We analyse a minimal supersymmetric standard model (MSSM) taking a minimal flavour violation (MFV) structure at the GUT scale. We evaluate the parameters at the electroweak scale taking into account the full flavour structure in the…

Certain string-inspired Z' models have non-universal interactions to three families of fermions and induced tree-level flavor-changing couplings. We use recent results on B_s-anti-B_s mixing to constrain the size of the flavor-changing…

A search for the decays Bs -> mu+ mu- and B0 -> mu+ mu- is performed with 0.37 fb^-1 of pp collisions at sqrt{s} = 7 TeV collected by the LHCb experiment in 2011. The upper limits on the branching fractions are BR (Bs -> mu+ mu-) < 1.6 x…

We investigate the possibility of observing the exotic decay mode of the top quark into the lightest stop ($\tilde t_1$) and neutralino ($\tilde\chi^0_1$) in the minimal supersymmetric standard model with R-parity at the upgraded Tevatron.…

A search for the rare decays $B^0_s \to\mu^+\mu^-$ and $B^0 \to\mu^+\mu^-$ is performed at the LHCb experiment. The data analysed correspond to an integrated luminosity of 1 fb$^{-1}$ of $pp$ collisions at a centre-of-mass energy of 7 TeV…

We extract a relatively precise value for the decay constant of the D+ meson by measuring B(D+ -> mu+ nu)=(4.40 +/- 0.66 {+0.09}{-0.12}) x 10^{-4}, using 281 inverse-pb of data taken on the psi(3770) resonance with the CLEO-c detector. We…

We report on searches for B^0_s to \mu^+ \mu^-, B^0_d to \mu^+ \mu^- decays and b to s \mu^+\mu^- transitions in exclusive decays of B mesons. Using 2 fb^{-1} of data collected by the CDF II detector we find upper limits on the branching…

The null search for the Higgs boson at the Tevatron implies strong constraints on heavy colored particles that increase the gluon-fusion induced production rate of the Higgs. We investigate the implications of the Tevatron exclusion limit…

The recent Tevatron result on the top quark forward-backward asymmetry, which deviates from its standard model prediction by 3.4$\sigma$, has prompted many authors to build new models to account for this anomaly. Among the various…