252 research outputs found

    Dynamical origin and the pole structure of X(3872)

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    The dynamical mechanism of channel coupling with the decay channels is applied to the case of coupled charmonium - DDDD^* states with JPC=1++J^{PC}=1^{++}. A pole analysis is done and the DDDD^* production cross section is calculated in qualitative agreement with experiment. The sharp peak at the D0D0D_0D^*_0 threshold and flat background are shown to be due to Breit-Wigner resonance, shifted by channel coupling from the original position of 3954 MeV for the 23P12^3P_1, QQˉQ\bar Q state. A similar analysis, applied to the n=2n=2, 3P2^3P_2, 1P1^1P_1, 3P0^3P_0, allows us to associate the first one with the observed Z(3930)Z(3930) J=2 and explains the destiny of 3P0^3P_0.Comment: 5 pages, 4 figures. Accepted for publication in Phys. Rev. Let

    The Hyperfine Splittings in Bottomonium and the Bq(q=n,s,c)B_q (q=n,s,c) Mesons

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    A universal description of the hyperfine splittings (HFS) in bottomonium and the Bq(q=n,s,c)B_q (q=n,s,c) mesons is obtained with a universal strong coupling constant αs(μ)=0.305(2)\alpha_s(\mu)=0.305(2) in a spin-spin potential. Other characteristics are calculated within the Field Correlator Method, taking the freezing value of the strong coupling independent of nfn_f. The HFS M(B)M(B)=45.3(3)M(B^*)- M(B)=45.3(3) MeV, M(Bs)M(Bs)=46.5(3)M(B_s^*) - M(B_s)=46.5(3) MeV are obtained in full agreement with experiment both for nf=3n_f=3 and nf=4n_f=4. In bottomonium, M(Υ(9460))M(ηb)=70.0(4)M(\Upsilon(9460))- M(\eta_b)=70.0(4) MeV for nf=5n_f=5 agrees with the BaBar data, while a smaller HFS, equal to 64(1) MeV, is obtained for nf=4n_f=4. We predict HFS M(Υ(2S))M(ηb(2S))=36(1)M(\Upsilon(2S))-M(\eta_b(2S))=36(1) MeV, M(Υ(3S))M(η(3S))=27(1)M(\Upsilon(3S))- M(\eta(3S))=27(1) MeV, and M(Bc)M(Bc)=57.5(10)M(B_c^*) - M(B_c)= 57.5(10) MeV, which gives M(Bc)=6334(1)M(B_c^*)=6334(1) MeV, M(Bc(21S0))=6865(5)M(B_c(2 {}^1S_0))=6865(5) MeV, and M(Bc(2S3S1))=6901(5)M(B_c^*(2S {}^3S_1))=6901(5) MeV.Comment: 5 pages revtex

    The possibility of Z(4430) resonance structure description in πψ\pi\psi' reaction

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    The possible description of Z(4430) as a pseudoresonance structure in πψ\pi \psi' reaction, is considered. The analysis is performed with single-scattering contribution to πψ\pi \psi' elastic scattering via DD1(2420)D^*D_1(2420) intermediate energy.Comment: 3 pages, 4 figure

    Large eddy simulation of turbulent flow and of pollutant transport in a street canyon

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    The work presents a non-steady three-dimensional eddy resolving model intended for the simulation of non-isothermal turbulent separation flows in street canyons. For a subgrid-scale turbulence parameterization, the Smagorinsky gradient model is used. The calculation results demonstrate the effects of pollutant source location, street canyon size, basic stream rate and wall temperature difference on air pollution in the canyon. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only
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