Related papers: Rare K- (vs.) B-decays

Experimental and theoretical progress concerning the rare decay pi0 to e+e- is briefly reviewed. It includes the latest data from KTeV and a new model independent estimate of the decay branching which show the deviation between experiment…

The rare B decays Bs(d)-->\mu\mu, B-->K*\mu\mu and Bs-->\phi\gamma are studied using up to \sim 0.41 fb^{-1} of pp collisions at \sqrt{s} = 7 TeV collected by the \lhcb experiment in 2010 and 2011. A search for the decays Bs(d)-->\mu\mu, is…

The rare $B\to K^{*}\nu\bar{\nu}$ decay when $K^{*}$ meson is longitudinally or transversely polarized is analysed in the context of the fourth generation model. A significant enhancement to the missing energy spectrum over the SM is…

I present some recent measurements of B meson decay rates to leptonic and charmless hadronic final states, as well as of CP-violation charge asymmetries and other features. I sketch the theoretical frameworks used to predict these, and…

Long-distance effects in exclusive rare semileptonic transitions B -> (K, K*) are analysed within a relativistic quark model. The meson transition form factors, describing the meson amplitudes of the effective weak Hamiltonian, are…

The theory of rare $K$ decays is reviewed, emphasizing short-distance processes and the prospects to probe the physics of flavour. A brief overview of the subject is presented, along with a more detailed discussion of the theory of…

We review some recent theoretical results on rare kaon decays. Particular attention is devoted to find Standard Model tests. This is theoretically easy in $K\to \pi \nu \bar{\nu}$, while a careful study of the long distance contributions is…

We present a concise review of the theoretical status of the rare semileptonic B -> X_s l^+ l^- decays in the standard model. Particular attention is thereby devoted to the recent theoretical progress concerning, on the one hand the…

We present preliminary results from a search for the flavor-changing neutral current decays B-->Kl^+l^- and B-->K^*(892)l^+l^- using a sample of 22.7 x 10^6 Upsilon(4S)-->B anti-B decays collected with the BABAR detector at the PEP-II B…

We study the decay B --> K l^+ l^- for l = e,mu,tau with a softly recoiling kaon, that is, for high dilepton invariant masses sqrt{q^2} of the order of the b-quark mass. This kinematic region can be treated within an operator product…

The supersymmetric contributions to the theoretically clean K+ --> pi+ nu nu bar, KL --> pi0 nu nu bar, KL --> pi0 e+ e- and KL --> pi0 mu+ mu- decays are briefly reviewed. Particular emphasis is laid on the information one could get on the…

We calculate the most interesting rare and CP-violating K and B decays in the Littlest Higgs model with T-parity. We give a collection of Feynman rules including v^2/f^2 contributions that are presented here for the first time and could…

Form factors of rare (B -> K_0*(1430) l^+ l^-$ decay) decay are calculated within three-point QCD sum rules, with (K_0* (1430)) being the p-wave scalar meson. The branching ratios are estimated when only short, as well as short and long…

Recent results from the first phase of the E787 experiment and an update on the current status are presented. From the first phase the limit on the K+ -> pi+ nu nu (pnn) branching ratio is BR(pnn) < 2.4e-9 (90%CL). An observation of the…

The flavor changing transitions in the c->u gamma, c->u gamma gamma and c->u l+ l- offer the possibility to search for new physics in the charm sector. We investigate dominant decay mechanisms in the radiative decays D->V gamma, D->P(V) l+…

We present a search for the rare decays B+ -> K+ nu nubar and B0 -> K0 nu nubar using 459 million BBbar pairs collected with the BaBar detector at the SLAC National Accelerator Laboratory. Flavor-changing neutral-current decays such as…

We review the status of rare kaon decays, concentrating on modes with sensitivity to short-distance flavour physics.

A bound on the angle gamma of the unitarity triangle is derived using experimental information on the CP-averaged branching ratios for the rare decays B^+- -> pi^+- K^0 and B^+- -> pi^0 K^+-. The theoretical description is cleaner than the…

The recent progress in search for T-violating transverse muon polarization in the decays K^+ --> pi^0 mu^+ nu and K^+ --> mu^+ nu gamma in the on-going experiment E246 at KEK is reported. Future prospects in polarization measurements are…

We calculate the charm quark contribution to the rare decay K+ -> pi+ nu anti-nu in the next-to-next-to-leading order of QCD. This new contribution reduces the theoretical uncertainty in the relevant parameter Pc from +/- 10.1% down to +/-…