118755762
About the creation of proton–antiproton pair at electron–positron collider in the energy range of ψ(3770) mass
The process of electron positron annihilation into proton-antiproton pair is considered within the vicinity of psi(3770) resonance. The interference between the pure electromagnetic intermediate state and the psi(3770) state is evaluated. It is shown that this interference is destructive and the relative phase between these two contributions is large (phi(0) approximate to 250 degrees). (C) 2014 The Authors. Published by Elsevier B.V.
118501601
First observation of CP violation and improved measurement of the branching fraction and polarization of B0→D*+D*− decays
We report the measurement of the branching fraction, the polarization, and the parameters of the time-dependent CP violation in B-0 -> D*(+) D*(-) decays using a data sample of 772 x 10(6)B (B) over bar pairs, collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We obtain a branching fraction of B = (7.82 +/- 0.38 +/- 0.63) x 10(-4), a CP-odd fraction of R-perpendicular to = 0.138 +/- 0.024 +/- 0.006 and, additionally, a fraction of the longitudinal component in the transversity base of R-0 = 0.624 +/- 0.029 +/- 0.011. The measured values of the parameters of the CP violation are SD*+ D*- = 0.79 +/- 0.13 +/- 0.03 and A(D*+ D*-) 0.15 +/- 0.08 +/- 0.04.
21907946
Search for T, CP, and CPT violation in B0-B0 mixing with inclusive dilepton events.
We report the results of a search for T, CP, CPT, and violation in B0-B0 mixing using an inclusive dilepton sample collected by the BABAR experiment at the PEP-II factory. Using a sample of 232 x 10(6) BB pairs, we measure the T and CP violation parameter |q/p| - 1 = (-0.8 +/- 2.7(stat) +/- 1.9(syst) x 10(-3), and the CPT and CP parameters Imz = (13.9 +/- 7.3(stat) +/- 3.2(syst)) x 10(-3) and Delta Gamma x Rez = (7.1 +/- 3.9(stat) +/- 2.0(stat)) x 10(-3) ps(-1). The statistical correlation between the measurements of Imz and Delta Gamma x Rez is 76%.
124556172
Searches for charmless decays $B^0 \to \eta \omega$, $B^0 \to \eta K^0$, $B^{+} \to \eta \rho^{+}$, and $B^{+} \to \eta^\prime \pi^{+}$
120311240
Observation of $J/\psi \rightarrow p\bar{p}a_{0}(980)$ at BESIII
Using $2.25\times10^{8}$ $J/\psi$ events collected with the BESIII detector at the BEPCII storage rings, we observe for the first time the process $J/\psi\rightarrow p\bar{p}a_{0}(980)$, $a_{0}(980)\rightarrow \pi^{0}\eta$ with a significance of $6.5\sigma$ ($3.2\sigma$ including systematic uncertainties). The product branching fraction of $J/\psi\rightarrow p\bar{p}a_{0}(980)\rightarrow p\bar{p}\pi^{0}\eta$ is measured to be $(6.8\pm1.2\pm1.3)\times 10^{-5}$, where the first error is statistical and the second is systematic. This measurement provides information on the $a_{0}$ production near threshold coupling to $p\bar{p}$ and improves the understanding of the dynamics of $J/\psi$ decays to four body processes.
120186826
Physics at BES-III
This physics book provides detailed discussions on important topics in $\tau$-charm physics that will be explored during the next few years at \bes3 . Both theoretical and experimental issues are covered, including extensive reviews of recent theoretical developments and experimental techniques. Among the subjects covered are: innovations in Partial Wave Analysis (PWA), theoretical and experimental techniques for Dalitz-plot analyses, analysis tools to extract absolute branching fractions and measurements of decay constants, form factors, and CP-violation and \DzDzb-oscillation parameters. Programs of QCD studies and near-threshold tau-lepton physics measurements are also discussed.
208023776
Strange magnetic form factor of nucleon in heavy baryon chiral effective approach at next to leading order
d ARC Centre of Excellence in Particle Physics at the Terascale, School of Chemistry & Physics, University of Adelaide, SA 5005, Australia Abstract The strange magnetic form factor of the nucleon is studied in the heavy baryon chiral effective approach at next to leading order. The one loop contributions from kaon and intermediate octet and decuplet hyperons are included, using finite-range-regularization to deal with the ultra-violet divergences. Drawing on an established connection between quenched and full QCD, this model makes it possible to predict the strange magnetic form factor under the hypothesis that for a dipole regulator mass Λ around 0.8 GeV, strangeness in the core is negligible. The strange magnetic form factor is found to be small and negative over a range of momentum transfer, while the strange magnetic moment is consistent with the best lattice QCD determinations.
121462931
Fermi LAT discovery of extended gamma-ray emission in the direction of supernova remnant W51C
The discovery of bright gamma-ray emission coincident with supernova remnant (SNR) W51C is reported using the Large Area Telescope (LAT) onboard the Fermi Gamma-ray Space Telescope. W51C is a middl ...
123240421
Strange hadronic matter in a modified quark-meson coupling model
Strange hadronic matter with nucleons,Lambda-hyperons and Xi-hyperons is studied by using a modified quark-meson coupling (MQMC) model in a mean-field approximation. The density dependence of the effective baryon masses as well as the saturation properties and stabilities of the strange hadronic matter are discussed. (C) 1999 Published by Elsevier Science B.V. All rights reserved.
18625699
Measurement of the cosmic ray e+ +e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope.
Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.
53311398
Chiral extrapolation of nucleon magnetic form factors
The extrapolation of nucleon magnetic form factors calculated within lattice QCD is investigated within a framework based upon heavy baryon chiral effective-field theory. All one-loop graphs are considered at arbitrary momentum transfer and all octet and decuplet baryons are included in the intermediate states. Finite range regularization is applied to improve the convergence in the quark-mass expansion. At each value of the momentum transfer (${Q}^{2}$), a separate extrapolation to the physical pion mass is carried out as a function of ${m}_{\ensuremath{\pi}}$ alone. Because of the large values of ${Q}^{2}$ involved, the role of the pion form factor in the standard pion-loop integrals is also investigated. The resulting values of the form factors at the physical pion mass are compared with experimental data as a function of ${Q}^{2}$ and demonstrate the utility and accuracy of the chiral extrapolation methods presented herein.