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Omega and eta meson production in p+p reactions at E_{kin} = 3.5 GeV  [PDF]
Khaled Teilab,for the HADES collaboration
Physics , 2010, DOI: 10.1142/S0217751X11052554
Abstract: We report on the exclusive production of omega and eta mesons in p+p reactions at 3.5 GeV beam kinetic energy. Production cross sections, angular distributions and Dalitz plots of both mesons were determined. Moreover, the relative contribution of the N(1535) resonance in eta production at this energy was evaluated. We conclude that eta mesons produced via N(1535) exihibit an isotropic angular distribution, whereas those produced directly show a strong anisotropic distribition. omega mesons show a slightly anisotropic angular distribition.
Evidence for Exotic J^{PC}=1^{-+} Meson Production in the Reaction pi- p --> eta pi- p at 18 GeV/c  [PDF]
E852 Collaboration,S. U. Chung et al
Physics , 1999, DOI: 10.1103/PhysRevD.60.092001
Abstract: Details of the analysis of the eta pi- system studied in the reaction pi^{-} p --> eta pi^{-} p at 18 GeV/c are given. Separate analyses for the 2 gamma and pi+ pi- pi0 decay modes of the eta are presented. An amplitude analysis of the data indicates the presence of interference between the a(2)(1320)- and a J^{PC}=1^{-+} wave between 1.2 and 1.6 GeV/c^2. The phase difference between these waves shows phase motion not attributable solely to the a(2)(1320)-. The data can be fitted by interference between the a(2)(1320)- and an exotic 1^{-+} resonance with M = 1370 +-16 +50 -30} MeV/c^2 and Gamma = 385 +- 40 +65 -105 MeV/c^2. Our results are compared with those of other experiments.
Measurement of the multi-hadron decays of omega, Ks and eta-mesons in heavy ion collisions at $\sqrt{s_{NN}}=200 GeV in the PHENIX experiment at RHIC  [PDF]
V. Riabov
Physics , 2007,
Abstract: The PHENIX experiment at RHIC measured $\omega$, $\eta$ and $K_{S}^{0}$-meson production at high $p_{T}$ in $p+p$, $d+Au$ and $Au+Au$ collisions at $\sqrt{s_{NN}}=200$ $GeV$. Measurements performed in different hadronic decay channels give consistent results. The measured ratios of all three mesons to $\pi^{0}$ are found to be flat as a function of $p_{T}$ in $p+p$ collisions and equal to $\omega/\pi^{0}=0.81\pm0.02\pm0.07$, $\eta/\pi^{0}=0.48\pm0.02\pm0.02$ and $K_{S}^{0}/\pi^{0}=0.45\pm0.01\pm0.05$. Nuclear modification factor measured for $\omega$-mesons in central Au+Au collisions is $R_{AA}=0.4\pm0.15$.
Search for B decays into eta' rho, eta' K*, eta' phi, eta' omega and eta' eta(') at Belle  [PDF]
J. Schümann,for the Belle Collaboration
Physics , 2007, DOI: 10.1103/PhysRevD.75.092002
Abstract: We report on a search for the exclusive two-body charmless hadronic B meson decays B-> eta' rho, B-> eta' K*, B-> eta' phi, B-> eta' omega and B->eta' eta('). The results are obtained from a data sample containing 535 x 10^6 BBbar pairs that were collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+ e- collider. We find no significant signals and report upper limits in the range 0.5-6.5 x 10^{-6} for all of the above decays.
Eta, Omega and Charmed Mesic Nuclei  [PDF]
K. Tsushima
Physics , 1998,
Abstract: Using the quark-meson coupling (QMC) model, we investigate theoretically whether $\eta$ and $\omega$ mesons form meson-nucleus bound states. We study several nuclei from $^{6}$He to $^{208}$Pb, including those which are the final nuclei in the proposed experiment at GSI. Results for the $\omega$ are compared with those of the Walecka model. Our results suggest that one should expect to find $\eta$- and $\omega$-nucleus bound states in all these nuclei. Furthermore, we investigate the possibility of charmed mesic nuclei. It is shown that the $D^-$ meson will inevitably form narrow bound states with $^{208}$Pb.
Mesons in Nuclei: eta and omega mesons  [PDF]
S. Schadmand
Physics , 2010, DOI: 10.1143/PTPS.186.373
Abstract: Data on the photoproduction of omega mesons on nuclei have been re-analyzed in search for in-medium modifications. The data were taken with the Crystal Barrel(CB)/TAPS detector system at the ELSA accelerator facility in Bonn. The extracted omega line shape was found to be sensitive to the background subtraction. In experiments at the tagged photon facility of the Mainz MAMI accelerator photoproduction of mesons from light nuclear targets (deuteron and 3He) has been studied. The experiments used the combined Crystal Ball/TAPS setup in Mainz. Measurements of eta- and pi0-photoproduction off a liquid 3He-target have been used for the search for the formation of eta-mesic 3He. The installation of the WASA detector at COSY opened a unique possibility to search for the 4He-eta bound state with high statistics and high acceptance. We are conducting a search via an exclusive measurement of the excitation function for the dd -> 3He p pi- reaction.
Study the isoscalar mesons $\eta_2(1870)$ and X(1870)
Bing, Chen;Wei, Ke-Wei;Zhang, Ailin
High Energy Physics - Phenomenology , 2013,
Abstract: An isoscalar resonance, X(1870), with a mass $M=1877.3\pm6.3(stat)^{+3.4}_{-7.4}(syst)$MeV and width $\Gamma=57\pm12(stat)^{+19}_{-4}(syst)$MeV was observed by the BesIII Collaboration recently. The mass of X(1870) is compatible with $\eta_2(1870)$ but the decay width is much smaller. In this paper, we analyzed the mass and the two-body strong decay of $\eta_2(1870)$ and X(1870). According to the mass spectra predicted by the Godfrey-Isgur potential model, X(1870) can be candidates of the states $f'_1(2^3P_1)$, $\eta'_2(1^1D_2)$ or $\eta_2(2^1D_2)$. In the Regge trajectories (RTs) framework, X(1870) favors the $\eta'(3^1S_0)$ and $f'_1(2^3P_1)$ assignments. However, the decay properties of $\eta'(3^1S_0)$, $f'_1(2^3P_1)$, $\eta'_2(1^1D_2)$ disagree with the experiments. The two-body strong decay widths indicate that $\eta_2(1870)$ and X(1870) maybe the two different resonant structures. $\eta_2(1870)$ could be assigned to the $\eta_2(2^1D_2)$ quarkonium as the first radical excited state of $\eta_2(1645)$. X(1870) favors a $\eta_H(0^+2^{-+})$ hybrid assignment. Some significant decay modes are suggested to test in future.
Are eta- and omega-nuclear states bound ?  [PDF]
K. Tsushima,D. H. Lu,A. W. Thomas,K. Saito
Physics , 1998, DOI: 10.1016/S0370-2693(98)01336-7
Abstract: We investigate theoretically whether it is feasible to detect $\eta$- and $\omega$-nucleus bound states. As well as the closed shell nuclei, $^{16}$O, $^{40}$Ca, $^{90}$Zr and $^{208}$Pb, we also investigate $^6$He, $^{11}$B and $^{26}$Mg, which are the final nuclei in the proposed experiment involving the (d,$^3$He) reaction at GSI. Potentials for the $\eta$ and $\omega$ mesons in these nuclei are calculated in local density approximation, embedding the mesons in the nucleus described by solving the mean-field equations of motion in the QMC model. Our results suggest that one should expect to find $\eta$- and $\omega$-nucleus bound states in all these nuclei.
New Baryons in the Delta eta and Delta omega Channels  [PDF]
Simon Capstick,W. Roberts
Physics , 1997, DOI: 10.1103/PhysRevD.57.4301
Abstract: The decays of excited nonstrange baryons into the final states Delta eta and Delta omega are examined in a relativized quark pair creation model. The wavefunctions and parameters of the model are fixed by previous calculations of N pi and N pi pi, etc., decays through various quasi-two body channels including N eta and N omega. Our results show that the combination of thresholds just below the region of interest and the isospin selectivity of these channels should allow the discovery of several new baryons in such experiments.
Isoscalar resonances with J^{PC}=1^{--} in e^+e^-annihilation  [PDF]
N. N. Achasov,A. A. Kozhevnikov
Physics , 1997, DOI: 10.1103/PhysRevD.57.4334
Abstract: The analysis of the vector isoscalar excitations in the energy range between 1 and 2 GeV of the $e^+e^-$ annihilation is presented for the final states $\pi^+\pi^-\pi^0$, $\omega\pi^+\pi^-$, $K^+K^-$, $K^0_SK^\pm\pi^\mp$ and $K^{\ast0}K^-\pi^++ c.c$. The effects of both the resonance mixing and the successive opening of multiparticle channels, with the energy dependent partial widths, are taken into account. The work extends our previous analysis hep-ph/9609216 of the vector isovector excitations and is aimed to compare the existing data with the predictions of the $q\bar q$ model. It is shown that this hypothesis does not contradict the data.
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