No Arabic abstract
We report the first observation of Y(5S) -> Y(nS) pi0 pi0 decays. The neutral partner of the Zb+-(10610), the Zb0(10610) decaying to Y(2,3S) pi0, is observed for the first time with a 6.5 sigma significance using a Dalitz analysis of Y(5S) -> Y(2,3S) pi0 pi0 decays. The results are obtained with a 121.4 fb^-1 data sample collected with the Belle detector at the Y(5S) resonance at the KEKB asymmetric-energy e+e- collider.
We report the first observation of Y(5S) -> Y(1,2S) pi0 pi0 decays. Evidence for the Zb0(10610) with 4.9sigma significance is found in a Dalitz plot analysis of Y(5S) -> Y(2S) pi0 pi0 decays. The results are obtained with a 121.4 fb^-1 data sample collected with the Belle detector at the Y(5S) resonance at the KEKB asymmetric-energy e+e- collider.
As first observed by the NA48/2 experiment at the CERN SPS, the $p0p0$ invariant mass (M00) distribution from $kcnn$ decay shows a cusp-like anomaly at M00=2m+, where m+ is the charged pion mass. An analysis to extract the pi pi scattering lengths in the isospin I=0 and I=2 states, a0 and a2, respectively, has been recently reported. In the present work the Dalitz plot of this decay is fitted to a new empirical parameterization suitable for practical purposes, such as Monte Carlo simulations of K+- -> pi+- pi0 pi0 decays.
Using the 9 inverse femtobarn data sample collected with the CLEO II.V detector at the Cornell Electron Storage Ring, we have studied the resonant substructure of the Cabibbo suppressed decay D0 -> pi+ pi- pi0. We observe significant contributions from the rho- pi+, rho+ pi-, rho0 pi0, and non-resonant channels, and present preliminary results of the amplitudes, phases, and fit fractions for these sub-modes. No evidence for the sigma(500) or more massive rho resonances was found. We observe no CP violation, finding Acp = 0.01 +0.09 -0.07 +- 0.09.
We report a measurement of the $B^0rightarrowpsi(2S)pi^0$ branching fraction based on the full $Upsilon(4S)$ data set of $772times10^{6}$ $Bbar{B}$ pairs collected by the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. We obtain $B(B^0rightarrowpsi(2S)pi^0) = (1.17pm0.17text{(stat)}pm0.08text{(syst)})times10^{-5}$. The result has a significance of 7.2 standard deviations and is the first observation of the decay $B^0rightarrowpsi(2S)pi^0$.
We report the observation of two narrow structures in the mass spectra of the pi+-Y(nS) (n=1,2,3) and pi+-hb(mP)(m$ (m=1,2) pairs that are produced in association with a single charged pion in Y(5S) decays. The measured masses and widths of the two structures averaged over the five final states are M_1=(10607.2+-2.0) MeV/c2, Gamma_1=(18.4+-2.4) MeV and M_2=(10652.2+-1.5) MeV/c2, Gamma_2=(11.5+-2.2) MeV. The results are obtained with a 121.4 1/fb data sample collected with the Belle detector in the vicinity of the Y(5S) resonance at the KEKB asymmetric-energy e+e- collider.