Related papers: On Unparticles and K+ to pi+ Missing Energy
We investigate the effect of unparticles in the pure annihilation type decays $B^- \to D_s^-\phi $ and $ D_s^- K^{*0}$. Since these decays have only annihilation contributions their branching ratios are expected to be very small in the…
We propose to perform a combined analysis of $B \to \pi\pi$ and $B_s \to K^+ K^-$ modes, in the framework of a global CKM fit. The method optimizes the constraining power of these decays and allows to derive constraints on NP contributions…
We study the reactions $K \rightarrow \pi \pi \nu \overline{\nu}$ within the minimal standard model. We use isospin symmetry to relate the matrix elements to the form factors measured in $K_{\ell 4}$. We argue that these modes are short…
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…
We present an analysis of the decay $D^{+} \to K^{-} \pi^+ e^+ \nu_e$ based on data collected by the BESIII experiment at the $\psi(3770)$ resonance. Using a nearly background-free sample of 18262 events, we measure the branching fraction…
We scrutinize the penguin dominated $ B_s \to K^+ K^-$ decay mode involving $b \to s$ quark level transition in family non-universal $Z^ \prime$ and vector-like down quark model. There is discrepancy in the standard model branching ratio…
We report a measurement of the exclusive $B^+$ meson decay to the final state $D_s^- K^+\pi^+$ using $520 \times 10^{6} B\bar{B}$ pairs collected near the $\Upsilon(4S)$ resonance, with the Belle detector at the KEKB asymmetric-energy…
We present preliminary measurements of branching fractions for the charmless two-body decays B0 -> pi+pi- and K+pi-, and a search for B0 -> K+K- using a data sample of approximately 227 million BBbar decays. Signal yields are extracted with…
The decay $B^- \to K^- K^- \pi^+$ has been sugested as a test for minimal supersymmetric standard model and for supersymmetric models with R-parity violating couplings, in view of its extreme smallnesss in the standard model. We calculate…
In this talk I describe work on computing non-leptonic matrix elements consistently with both long and short distance contributions included. On the simpler example of the $\pi^+$-$\pi^0$ mass difference I explain in detail the matching…
Using chiral low energy theorems and elastic unitarity assumption, the $\tau\to\pi K \nu $ decay is investigated. The vector and scalar $\pi K$ form factors are calculated. It is found that the $\pi K$ spectrum is dominated by the $K^*$…
The fully differential angular distribution for the rare flavor-changing neutral current decay {\bar B}_d^0 -> {\bar K}^{*0} (-> K^- \pi^+) e+ e- is studied. The emphasis is placed on accurate treatment of the contribution from the…
From an analysis of the ionisation energy loss of charged particles selected from a sample of 147926 e+e- -> tau+tau- candidates recorded in the OPAL detector at e+e- centre-of-mass energies near the Z0 resonance, we determine the branching…
Using 535 x 10^6 B-meson pairs collected by the Belle detector at the KEKB e+ e- collider, we measure branching fractions of (7.16 +/- 0.10(stat) +/- 0.60(syst)) x 10^-4 for B+ -> J/psi K+ pi+ pi- and (4.31 +/- 0.20(stat) +/- 0.50(syst)) x…
Motivated by some new experimental and theoretical efforts, we update the theoretical analysis of the electron-positron energy asymmetry, which arises, in K_L --> pi0 e+ e-, from the two-photon intermediate state in the standard model. It…
After discussion of mechanisms of lepton number violation, we consider meson decays $K^+ \to\pi^ - \ell ^ + \ell '^ +$ and $D^ + \to K^ - \ell ^ + \ell '^ +$ ($\ell,\ell ' = e,\mu $) with $\Delta L= 2$ in the Standard Model extended by…
Recent experimental data for the differential decay distribution of the decay $\tau^-\to\nu_\tau K_S\pi^-$ by the Belle collaboration are described by a theoretical model which is composed of the contributing vector and scalar form factors…
The coupling of an unparticle operator O_U to Standard Model particles opens up the possibility of unparticle decays into standard model fields. We study this issue by analyzing the pole structure (and spectral function) of the unparticle…
In this paper we consider the decay $D^+\to\pi^+\ell^+\ell^-$, addressing in particular the resonance contributions as well as the relatively large contributions from the weak annihilation diagrams. For the weak annihilation diagrams we…
In this note we show how improved theoretical analysis combined with recent experimental data coming from NA48/2 concerning $K^+ \to \pi^+ \pi^0 \gamma$ decay shed light on the dynamics of the $s \rightarrow d \gamma$ transition.…