A Systematic Study of Power Corrections from World Deep Inelastic Scattering Measurements

By performing an analysis in moment space using high statistics DIS world data, we extract the values of both the QCD parameter $\Lambda^{(4)}_{\bar{MS}}$ up to NLO and of the power corrections to the proton structure function, $F_2$. At variance with previous analyses, the use of moments allows us to extend the kinematical range to larger values of $x$, where we find that power corrections are quantitatively more important. Our results are consistent with the $n$ dependence predicted by IR renormalon calculations. We discuss preliminary results on nuclear targets with the intent of illustrating a possible strategy to disentangle power corrections ascribed to IR renormalons from the ones generated dynamically e.g. from rescattering in the final state. The latter appear to be modified in nuclear targets.Comment: 4 pages, 2 figures, LateX with espcrc2 and epsfi

Nuclear medium effects in ν(νˉ)\nu(\bar\nu)-nucleus deep inelastic scattering

We study the nuclear medium effects in the weak structure functions $F_2(x,Q^2)$ and $F_3(x,Q^2)$ in the deep inelastic neutrino/antineutrino reactions in nuclei. We use a theoretical model for the nuclear spectral functions which incorporates the conventional nuclear effects, such as Fermi motion, binding and nucleon correlations. We also consider the pion and rho meson cloud contributions calculated from a microscopic model for meson-nucleus self-energies. The calculations have been performed using relativistic nuclear spectral functions which include nucleon correlations. Our results are compared with the experimental data of NuTeV and CDHSW.Comment: 24 pages, 14 figure

Emulsion Chamber with Big Radiation Length for Detecting Neutrino Oscillations

A conceptual scheme of a hybrid-emulsion spectrometer for investigating various channels of neutrino oscillations is proposed. The design emphasizes detection of $\tau$ leptons by detached vertices, reliable identification of electrons, and good spectrometry for all charged particles and photons. A distributed target is formed by layers of low-Z material, emulsion-plastic-emulsion sheets, and air gaps in which $\tau$ decays are detected. The tracks of charged secondaries, including electrons, are momentum-analyzed by curvature in magnetic field using hits in successive thin layers of emulsion. The $\tau$ leptons are efficiently detected in all major decay channels, including \xedec. Performance of a model spectrometer, that contains 3 tons of nuclear emulsion and 20 tons of passive material, is estimated for different experimental environments. When irradiated by the $\nu_\mu$ beam of a proton accelerator over a medium baseline of $\sim 1$ km/GeV, the spectrometer will efficiently detect either the \omutau and \omue transitions in the mass-difference region of $\Delta m^2 \sim 1$ eV$^2$, as suggested by the results of LSND. When exposed to the neutrino beam of a muon storage ring over a long baseline of $\sim$ 10-20 km/GeV, the model detector will efficiently probe the entire pattern of neutrino oscillations in the region $\Delta m^2 \sim 10^{-2}-10^{-3}$ eV$^2$, as suggested by the data on atmospheric neutrinos.Comment: 34 pages, 8 figure

Determination of the high-twist contribution to the structure function xF3νNxF^{\nu N}_3

We extract the high-twist contribution to the neutrino-nucleon structure function $xF_3^{(\nu+\bar{\nu})N}$ from the analysis of the data collected by the IHEP-JINR Neutrino Detector in the runs with the focused neutrino beams at the IHEP 70 GeV proton synchrotron. The analysis is performed within the infrared renormalon (IRR) model of high twists in order to extract the normalization parameter of the model. From the NLO QCD fit to our data we obtained the value of the IRR model normalization parameter $\Lambda^2_{3}=0.69\pm0.37~({\rm exp})\pm0.16~({\rm theor})~{\rm GeV}^2$. We also obtained $\Lambda^2_{3}=0.36\pm0.22~({\rm exp})\pm0.12~({\rm theor})~{\rm GeV}^2$ from a similar fit to the CCFR data. The average of both results is $\Lambda^2_{3}=0.44\pm0.19~({\rm exp})~{\rm GeV}^2$.Comment: preprint IHEP-01-18, 7 pages, LATEX, 1 figure (EPS

Target Mass Corrections for Polarized Structure Functions and New Sum Rules

The target mass corrections are calculated for all structure functions of neutral and charged current deep inelastic scattering in lowest order in the coupling constant. Representations of the correction to the twist--2 and twist--3 contributions are derived both in Mellin-$n$ and $x$-space. The impact of the target mass corrections on the general relations between the twist--2 and twist--3 parts of the structure functions is studied and three new relations between the twist--3 contributions are derived.Comment: 34 pages LATEX, 1 style fil

A measurement of alphas(Q2)alpha_s(Q^2) from the Gross-Llewellyn Smith Sum Rule

We extract a set of values for the Gross-Llewellyn Smith sum rule at different values of 4-momentum transfer squared ($Q^{2}$), by combining revised CCFR neutrino data with data from other neutrino deep-inelastic scattering experiments for $1 < Q^2 < 15 GeV^2/c^2$. A comparison with the order $\alpha^{3}_{s}$ theoretical predictions yields a determination of $\alpha_{s}$ at the scale of the Z-boson mass of $0.114 \pm^{.009}_{.012}$. This measurement provides a new and useful test of perturbative QCD at low $Q^2$, because of the low uncertainties in the higher order calculations.Comment: 4 pages, 4 figure

Search for the X(1812) in B±→K±ωϕB^{\pm} \to K^{\pm} \omega \phi

We report on a search for the X(1812) state in the decay $B^{\pm} \to K^{\pm} \omega \phi$ with a data sample of $657\times10^6$ $B\bar{B}$ pairs collected with the Belle detector at the KEKB $e^+e^-$ collider. No significant signal is observed. An upper limit ${\cal B}(B^{\pm} \to K^{\pm} X(1812),X(1812) \to \omega \phi)<3.2\times 10^{-7}$ (90% C.L.) is determined. We also constrain the three-body decay branching fraction to be ${\cal B}(B^{\pm} \to K^{\pm} \omega \phi)$ $<$ 1.9 $\times 10^{-6}$ (90% C.L.).Comment: 5pages,2 figures(3 figure files). submitted to PRD(RC

Observation of B+->Lambda_c+Lambda_c-K+ and B0->Lambda_c+Lambda_c^-K0 decays

We report first measurements of the doubly charmed baryonic B decays B->Lambda_c+Lambda_c-K. The B+->Lambda_c+Lambda_c-K+ decay is observed with a branching fraction of (6.5+1.0-0.9+-1.1+-3.4)x10^{-4} and a statistical significance of 15.4sigma. The B0->Lambda_c+Lambda_c-K0 decay is observed with a branching fraction of (7.9+2.9-2.3+-1.2+-4.2)x10^{-4} and a statistical significance of 6.6sigma. The branching fraction errors are statistical, systematic, and the error resulting from the uncertainty of Lambda_c+->pK-pi+ decay branching fraction. The analysis is based on 357fb-1 of data accumulated at the Y(4S) resonance with the Belle detector at the KEKB asymmetric e+e- collider.Comment: 10 pages, 3 figure