124556172
Searches for charmless decays $B^0 \to \eta \omega$, $B^0 \to \eta K^0$, $B^{+} \to \eta \rho^{+}$, and $B^{+} \to \eta^\prime \pi^{+}$
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.
120509600
The Upper limit of the e+ e- partial width of X(3872)
Abstract The e + e − decay partial width of the recently observed state, X (3872), is estimated using the ISR data collected at s =4.03  GeV in e + e − annihilation experiment by BES at BEPC. It is found that Γ e + e − B π + π − J/ψ  eV at 90% C.L. if the J PC of X (3872) is 1 −− . Together with the potential models and other information, we conclude that X (3872) is very unlikely to be a vector state.
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.
53857242
Study of the near-threshold ωϕ mass enhancement in doubly OZI-suppressed J/ψ→γωϕ decays
A 2:25 x 10(8) J/psi event sample accumulated with the BESIII detector is used to study the doubly Okubo-Zweig-Iizuka-suppressed decay modes J/psi -> gamma omega phi, omega -> pi(+)pi(-)pi(0), phi -> K+K-. A strong deviation (> 30 sigma) from three-body J/psi -> gamma omega phi phase space is observed near the omega phi mass threshold that is consistent with a previous observation reported by the BESII experiment. A partial wave analysis with a tensor covariant amplitude that assumes that the enhancement is due to the presence of a resonance, the X(1810), is performed and confirms that the spin-parity of the X(1810) is 0(++). The mass and width of the X(1810) are determined to be M = 1795 +/- 7(stat)(-5)(+13) (syst) +/- 19(mod) MeV/c(2) and Gamma = 95 +/- 10(stat)(-34)(+21)(syst) +/- 75(mod) MeV/c(2), respectively, and the product branching fraction is measured to be B(J/psi -> gamma X(1810)) x B(X(1810) -> omega phi) = (2.00 +/- 0.08(stat)(-1.00)(+0.45)(syst) +/- 1.30(mod)) x 10(-4). These results are consistent within errors with those of the BESII experiment. DOI: 10.1103/PhysRevD.87.032008
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.
126219189
Sidereal daily variation of approximately 10-TeV cosmic ray intensity observed by the Tibet air-shower arrays
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 .
6479982
Franck‐Condon principle for heavy‐quark hadron decays
The Franck‐Condon principle governing molecular electronic transitions is utilized to study heavy‐quark hadron decays. This provides a direct assessment of the wavefunction of the parent hadron if the momentum distribution of the open‐flavor decay products is measured. Model‐independent results include an experimental distinction between quarkonium and exotica (hybrids, tetraquarks…), an off‐plane correlator signature for tetraquarks and a direct probe of the sea quark orbital wavefunction relevant in the discussion of 3S1 or 3P0 decay mechanisms.
117796835
Static three-body potential in baryons
The first principle of quantum chromodynamics is used to calculate the static perturbative three-body potential between three valence quarks in baryons, which is gauge invariant and flavor-dependent, and of magnitude of the same order as the next non-leading static q-q potential. Its effect on an S-state baryon composed of three valence quarks of equal mass may be viewed as a slight increase of the constituent quark masses with respect to those in mesons.
120920880
Strange hadronic matter in an effective model
Strange hadronic matter with nucleons, Λ-hyperon and Ξ-hyperon is studied using an effective model in the 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.