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Z.G. Zhao
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We report the preliminary R values for all the 85 energy points scanned in the energy region of 2-5 GeV with the upgraded Beijing Spectrometer (BESII) at Beijing Electron Positron Collider (BEPC). Preliminary results from the J/psi data collected with both BESI and BESII are presented. Measurements of the branching fraction of the psi(2S) decays and the psi(2S) resonance parameters are reported. The future plans, i.e. significantly upgrade the machine and detector are also discussed.
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We present the numu to nue appearance and the numu disappearance results, using a total of 1.43 x 10^{20} protons on target collected with the T2K experiment. T2K is long baseline neutrino experiment in Japan with detectors located at J-PARC, Tokai, and at Kamioka in the Gifu Prefecture, situated 295 km away from J-PARC. The muon neutrino beam is produced and measured at the near detectors at J-PARC whilst the neutrino rates after oscillation are measured with the Super-Kamiokande detector, at Kamioka. A total of six events pass all the selection criteria for numu to nue oscillations at the far detector Super-Kamiokande, leading to 0.03(0.04) < sin^2 2theta_{13} < 0.28(0.34) for deltaCP = 0 and normal (inverted) hierarchy at 90% C.L. The numu disappearance analysis excludes no oscillations at 4.3 sigma. At 90% C.L., the best fit values are sin^2 2theta_{23} > 0.84 and 2.1 x 10^{-3} < Delta m^2_{23} (eV^2) < 3.1 x 10^{-3}. Finally, we present an overview of the T2K plans from 2011 onwards.
Using 58 million $J/psi$ and 14 million $psi(2S)$ events collected by the BESII detector at the BEPC, branching fractions or upper limits for the decays $J/psi$ and $psi(2S) to Lambda bar{Lambda} pi^0$ and $Lambda bar{Lambda} eta$ are measured, and the decays of $J/psi$ and $psi(2S)$ to $n K^0_S bar{Lambda}+c.c.$ are observed and measured for the first time. Finally, $R$ measurement data taken with the BESII detector at center-of-mass energies between 3.7 and 5.0 GeV are fitted to determine resonance parameters of the high mass charmonium states, $psi(3770)$, $psi(4040)$, $psi(4160)$, and $psi(4415)$. The Beijing Electron Collider is being upgraded to a two-ring collider (BEPCII) with a design luminosity of $1 times 10^{33}$cm$^{-2}$ s$^{-1}$ at 3.89 GeV and will operate between 2 and 4.2 GeV in the center of mass. With this luminosity, the new BESIII detector will beable to collect, for example, 10 billion $J/psi$ events in one year of running. BEPCII and BESIII are currently nearing completion, and commissioning of both is expected to begin in mid-2008.
There are about 33, 6.5 and 1.0 pb$^{-1}$ of $e^+e^-$ annihilation data have been taken around the center-of-mass energies of $sqrt s=$ 3.773 GeV, at $sqrt s=$ 3.650 GeV and at $sqrt s=$ 3.6648 GeV, respectively, with the BES-II detector at the BEPC collider. By analyzing these data sets, we have measured the branching fraction for $psi(3770)to$ non-$Dbar D$ by several different methods; and have observed an anomalous line shape of $sigma^{e^+e^-to{rm hadrons}}$ in energy region from 3.65 to 3.87 GeV; and have measured the line shapes of the $D^+D^-$, $D^0bar D^0$ and $Dbar D$ production and together with the ratios of the production rates of $D^+D^-$ and $D^0bar D^0$ in $e^+e^-$ annihilation around the $psi(3770)$ resonance.
The Borexino experiment, located in the Gran Sasso National Laboratory, is an organic liquid scintillator detector conceived for the real time spectroscopy of low energy solar neutrinos. The data taking campaign phase I (2007 - 2010) has allowed the first independent measurements of 7Be, 8B and pep fluxes as well as the first measurement of anti-neutrinos from the earth. After a purification of the scintillator, Borexino is now in phase II since 2011. We review here the recent results achieved during 2013, concerning the seasonal modulation in the 7Be signal, the study of cosmogenic backgrounds and the updated measurement of geo-neutrinos. We also review the upcoming measurements from phase II data (pp, pep, CNO) and the project SOX devoted to the study of sterile neutrinos via the use of a 51Cr neutrino source and a 144Ce-144Pr antineutrino source placed in close proximity of the active material.
The paper discusses future experiments at super $B$ factories. It presents the physics motivation and the tools, accelerators and detectors, and reviews the status of the two projects, SuperKEKB/Belle-II in Japan and SuperB in Italy.
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