119283952
Measurements of the masses and widths of the $\Sigma_{c}(2455)^{0/++}$ and $\Sigma_{c}(2520)^{0/++}$ baryons
We present measurements of the masses and decay widths of the baryonic states (2455) and (2520) using a data sample corresponding to an integrated luminosity of 711 fb- 1 collected with the detector at the KEKB e e- asymmetric- energy collider operating at the.(4S) resonance. We report the mass differences with respect to the A(c) baryon.
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.
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.
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 $B^{+} \to \eta^\prime \pi^{+}$
119108965
Coulomb gauge model for hidden charm tetraquarks
Abstract The spectrum of tetraquark states with hidden charm is studied within an effective Coulomb gauge Hamiltonian approach. Of the four independent color schemes, two are investigated, the ( q c ¯ ) 1 ( c q ¯ ) 1 singlet–singlet (molecule) and the ( q c ) 3 ( q ¯ c ¯ ) 3 triplet–triplet (diquark), for selected J PC states using a variational method. The predicted masses of triplet–triplet tetraquarks are roughly a GeV heavier than the singlet–singlet states. There is also an interesting flavor dependence with ( q q ¯ ) 1 ( c c ¯ 1 ) states about half a GeV lighter than ( q c ¯ ) 1 ( q ¯ c ) 1 . The lightest 1 + + and 1 − − predictions are in agreement with the observed X ( 3872 ) and Y ( 4008 ) masses suggesting they are molecules with ω J / ψ and η h c , rather than D ⁎ D ¯ ⁎ and D D ¯ , type structure, respectively. Similarly, the lightest isovector 1 + + molecule, having a ρ J / ψ flavor composition, has mass near the recently observed charged Z c ( 3900 ) value. These flavor configurations are consistent with observed X , Y and Z c decays to π π J / ψ .
123069781
Thermodynamical properties of nuclear matter in a model with vector meson self-interaction
The relativistic model with vector meson self-interaction (Bodmer A R 1991 Nuc. Phys. A 526 703) is extended to asymmetric nuclear matter at finite temperature. The extended model is then used to discuss the liquid-gas phase transition in nuclear matter and the Coulomb instability of hot nuclei. It is found that the limiting temperature and the critical temperature depend on the parameter sets of this model considerably. The role the meson plays in asymmetric nuclear matter is also examined.
84836167
Constraints on dark matter models from a Fermi LAT search for high-energy cosmic-ray electrons from the Sun
During its first year of data taking, the Large Area Telescope (LAT) onboard the Fermi Gamma-Ray Space Telescope has collected a large sample of high-energy cosmic-ray electrons and positrons (CREs ...
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.
17755013
Coulomb gauge approach to scalar hadrons
The Coulomb gauge model, involving an effective QCD Hamiltonian in the Coulomb gauge, is applied to scalar hadrons. Mass predictions are presented for both conventional qq meson and qqqq tetra‐quark states. Mixing matrix elements between these states were also computed and diagonalized to provide a reasonable description of the scalar spectrum below 2 GeV.