0000000000120378

AUTHOR

J. J. Xie

(B)over-bar(0), B- and (B)over-bar(S)(0) decays into J/psi and K (K)over-bar or pi eta

12 pages.- 6 figures.- v2: discussion added, references added

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Study of the f(2)(1270), f '(2)(1525), and (K)over-bar(2)*(1430), f(0)(1370) and f(0)(1710) production from psi(nS) and Upsilon(nS) decays

Based on previous studies that support the important role of the f(2)(1270), f'(2)(1525), and (K) over bar (2)*(1430) resonances in the J/psi[psi(2S)] -> phi(omega)VV decays, we make an analysis of the analogous decays of Upsilon(1S) and Upsilon(2S), taking into account recent experimental data. In addition, we study the J/psi and psi(2S) radiative decays and we also made predictions for the radiative decay of Upsilon(1S) and Upsilon(2S) into gamma f(2)(1270), gamma f(2)'(1525), gamma f(0)(1370) and gamma f(0)(1710) comparing with the recent results of a CLEO experiment. We can compare our results for ratios of decay rates with eight experimental ratios and find agreement in all but one cas…

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Interaction of vector mesons with baryons and vectors in the nuclear medium

In this talk we present a short review of recent developments concerning the interaction of vector mesons with baryons and with nuclei. We begin with the hidden gauge formalism for the interaction of vector mesons, then review results for vector baryon interaction and in particular the resonances which appear as composite states, dynamically generated from the interaction of vector mesons with baryons. New developments concerning the mixing of these states with pseudoscalars and baryons are also reported. We include some discussion on the $5/2^+$ $\Delta$ resonances around 2000 MeV, where we suggest that the $\Delta(2000)5/2^+$ resonance, which comes in the PDG from averaging a set of reson…

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(B)over-bar(0) and (B)over-bar(s)(0) decays into J/psi and f(0)(1370), f(0)(1710), f(2)(1270), f(2)'(1525), K-2*(1430)

We make predictions for the ratios of branching fractions of (B) over bar (0) and (B) over bar (0)(s) decays into J/psi and the scalar mesons f(0)(1370), f(0)(1710) or tensor mesons f(2)(1270), f(2)'(1525), K-2*(1430). The theoretical approach is based on results of chiral unitary theory where these resonances are shown to be generated from the vector meson-vector meson interaction. Eight independent ratios can be predicted, and comparison is made with the recent data on (B) over bar (0)(s) decay into J/psi f(2)'(1525) versus the (B) over bar (0)(s) decay into J/psi f(2)(1270).

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Faddeev fixed-center approximation to the N K K(bar) system and the signature of a N*(1920)(1/2+) state

We perform a calculation for the three body NK¯K scattering amplitude by using the fixed center approximation to the Faddeev equations, taking the interaction between N and K¯, N and K, and K¯ and K from the chiral unitary approach. The resonant structures show up in the modulus squared of the three body scattering amplitude and suggest that a NK¯K hadron state can be formed. Our results are in agreement with others obtained in previous theoretical works, which claim a new N∗ resonance around 1920 MeV with spin-parity JP=1/2+. The existence of these previous works allows us to test the accuracy of the fixed center approximation in the present problem and sets the grounds for possible applic…

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The DN, pi Sigma(c) interaction in finite volume and the Lambda(c)(2595) resonance

In this work the interaction of the coupled channels DN and pi Sigma(c) in an SU(4) extrapolation of the chiral unitary theory, where the Lambda(c)(2595) resonance appears as dynamically generated from that interaction, is extended to produce results in finite volume. Energy levels in the finite box are evaluated and, assuming that they would correspond to lattice results, the inverse problem of determining the phase shifts in the infinite volume from the lattice results is solved. We observe that it is possible to obtain accurate pi Sigma(c) phase shifts and the position of the Lambda(c)(2595) resonance, but it requires the explicit consideration of the two coupled channels. We also observ…

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Delta rho pi Interaction Leading to N* and Delta* Resonances

We have performed a calculation for the three body Δρπ system by using the fixed center approximation to Faddeev equations, taking the interaction between Δ and ρ, Δ andπ, and ρ and π from the chiral unitary approach. We find several peaks in the modulus squared of the three-body scattering amplitude, indicating the existence of resonances, which can be associated to known I=1/2,3/2 and JP=1/2+,3/2+ and 5/2+ baryon states.

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The K K bar π decay of the f1 (1285) and its nature as a K* K bar - cc molecule

We investigate the decay of f1 (1285) → πK K bar with the assumption that the f1 (1285) is dynamically generated from the K* K bar - cc interaction. In addition to the tree level diagrams that proceed via f1 (1285) →K* K bar - cc → πK K bar , we take into account also the final state interactions of K K bar → K K bar and πK → πK. The partial decay width and mass distributions of f1 (1285) → πK K bar are evaluated. We get a value for the partial decay width which, within errors, is in fair agreement with the experimental result. The contribution from the tree level diagrams is dominant, but the final state interactions have effects in the mass distributions. The predicted mass distributions …

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Hadron Dynamics with Vector Mesons: Matching Theory and Experiment to Identify New Resonances

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(B)over-bar(0) decay into D-0 and f(0)(500), f(0)(980), a(0)(980), rho and (B)over-bar(s)(0) decay into D-0 and kappa(800), K*(0)

We make predictions for ratios of branching fractions of (B) over bar (0) decays into D-0 and the scalar mesons f(0)(500), f(0)(980), a(0)(980), plus (B) over bar (0)(s) decay into D-0 and kappa(800). We also compare the pi(+)pi(-) production in the scalar channel with that observed in the rho channel and make predictions for the (B) over bar (0)(s) decay into D-0 and K*(892), comparing the strength of this channel with that of kappa(800) production. The work is based on results of the chiral unitary approach where the scalar resonances are generated from the pseudoscalar-pseudoscalar interaction. Up to an arbitrary normalization, the mass distributions and rates for decays into the scalar …

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Role of the N * (2080) resonance in the (gamma)over-right-arrowp -> K+ Lambda(1520) reaction

We investigate the Lambda (1520) photoproduction in the (gamma) over right arrowp -> K+ Lambda(1520) reaction within the effective Lagrangian method near threshold. In addition to the 'background' contributions from the contact, t-channel K-exchange, and s-channel nucleon pole terms, which were already considered in previous studies, the contribution from the nucleon resonance N*(2080) (spin-parity J(P) = 3/2(-)) is also considered. We show that the inclusion of the nucleon resonance N*(2080) leads to a fairly good description of the new LEPS differential cross-section data, and that these measurements can be used to determine some of the properties of this latter resonance. However, seriou…

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Predictions for the X(YZ) and X(YZ) with X(4160), Y(3940), Z(3930)

We investigate the decay of and with R being the , , resonances. Under the assumption that these states are dynamically generated from the vector-vector interaction, as has been concluded from several theoretical studies, we use a reaction mechanism of quark production at the elementary level, followed by hadronization of one final pair into two vectors and posterior final state interaction of this pair of vector mesons to produce the resonances. With this procedure we are able to predict five ratios for these decays, which are closely linked to the dynamical nature of these states, and also predict the order of magnitude of the branching ratios which we find of the order of , well within t…

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Plausible explanation for the Delta(5/2)+(2000) puzzle

From a Faddeev calculation for the π−(Δρ)N5/2−(1675) system we show the plausible existence of three dynamically generated I(JP)=3/2(5/2+) baryon states below 2.3 GeV whereas only two resonances, Δ5/2+(1905)(∗∗∗∗) and Δ5/2+(2000)(∗∗), are cataloged in the Particle Data Book Review. Our results give theoretical support to data analyses extracting two distinctive resonances, Δ5/2+(∼1740) and Δ5/2+(∼2200), from which the mass of Δ5/2+(2000)(∗∗) is estimated. We propose that these two resonances should be cataloged instead of Δ5/2+(2000). This proposal gets further support from the possible assignment of the other baryon states found in the approach in the I=1/2,3/2 with JP=1/2+,3/2+,5/2+ secto…

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A case in favor of the $N^*(1700)(3/2^-)$

Using an interaction extracted from the local hidden gauge Lagrangians, which brings together vector and pseudoscalar mesons, and the coupled channels $\rho N$ (s-wave), $\pi N$ (d-wave), $\pi \Delta$ (s-wave) and $\pi \Delta$ (d-wave), we look in the region of $\sqrt s =1400-1850$ MeV and we find two resonances dynamically generated by the interaction of these channels, which are naturally associated to the $N^*(1520) (3/2^-)$ and $N^*(1700) (3/2^-)$. The $N^*(1700) (3/2^-)$ appears neatly as a pole in the complex plane. The free parameters of the theory are chosen to fit the $\pi N$ (d-wave) data. Both the real and imaginary parts of the $\pi N$ amplitude vanish in our approach in the vic…

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Signature of an h(1) state in the J/psi -> eta h(1) -> eta K*(0)(K)over-bar*(0) decay

The BES data on the J/psi -> eta K*(0)(K) over bar*(0) reaction show a clear enhancement in the K*(0)(K) over bar*(0) mass distribution close to the threshold of this channel. Such an enhancement is usually a signature of an L = 0 resonance around threshold, which in this case would correspond to an h1 state with quantum numbers I-G(J(Pc))= 0(-)(1(+-)). A state around 1800 MeV results from the interaction of the K*TC* using the local hidden gauge approach. We show that the peak observed in J/psi -> eta K*(0)(K) over bar*(0) naturally comes from the creation of this h(1) state with mass and width around 1830 MeV and 110 MeV, respectively. A second analysis, model independent, corroborates th…

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The pp -> p Lambda K(+) and pp -> p Sigma(0)K(+) reactions with chiral dynamics

We report on a theoretical study of the pp->p Lambda K+ and pp->p Sigma0 K+ reactions near threshold using a chiral dynamical approach. The production process is described by single-pion and single-kaon exchange. The final state interactions of nucleon-hyperon, K-hyperon and K-nucleon systems are also taken into account. We show that our model leads to a fair description of the experimental data on the total cross section of the pp->p Lambda K+ and pp->p Sigma0 K+ reactions. We find that the experimental observed strong suppression of Sigma0 production compared to Lambda production at the same excess energy can be explained. However, ignorance of phases between some amplitudes does not allo…

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