Eulogi Oset

Prediction of Narrow N* and {Lambda}* Resonances with Hidden Charm above 4 GeV

The interaction between various charmed mesons and charmed baryons is studied within the framework of the coupled-channel unitary approach with the local hidden gauge formalism. Several meson-baryon dynamically generated narrow N* and Λ* resonances with hidden charm are predicted with mass above 4 GeV and width smaller than 100 MeV. The predicted new resonances definitely cannot be accommodated by quark models with three constituent quarks and can be looked for in the forthcoming PANDA/FAIR experiments.

Dynamically generated resonances from the vector octet-baryon octet interaction

We study the interaction of vector mesons with the octet of stable baryons in the framework of the local hidden gauge formalism using a coupled-channels unitary approach. We examine the scattering amplitudes and their poles, which can be associated to known JP = 1/2-, 3/2- baryon resonances, in some cases, or give predictions in other ones. The formalism employed produces doublets of degenerate JP = 1/2-, 3/2- states, a pattern which is observed experimentally in several cases. The findings of this work should also be useful to guide present experimental programs searching for new resonances, in particular in the strange sector where the current information is very poor.

Couplings in coupled channels versus wave functions: application to the X(3872) resonance

This work is partly supported by DGI and nFEDER funds, under contract FIS2006-03438, FIS2008-01143/FIS and PIE-CSIC 200850I238 and the Junta nde Andalucia grant no. FQM225-05. We acknowledge nthe support of the European Community-Research nInfrastructure Integrating Activity ”Study of Strongly nInteracting Matter” (acronym HadronPhysics2, Grant nAgreement n. 227431) under the Seventh Framework nProgramme of EU. Work supported in part by DFG n(SFB/TR 16, ”Subnuclear Structure of Matter”).

Vector meson-vector meson interaction in a hidden gauge unitary approach

The formalism developed recently to study vector meson-vector meson interaction, and applied to the case of {rho}{rho}, is extended to study the interaction of the nonet of vector mesons among themselves. The interaction leads to poles of the scattering matrix corresponding to bound states or resonances. We show that 11 states (either bound or resonant) get dynamically generated in nine strangeness-isospin-spin channels. Five of them can be identified with those reported in the PDG, i.e., the f{sub 0}(1370), f{sub 0}(1710), f{sub 2}(1270), f{sub 2}{sup }(1525), and K{sub 2}*(1430). The masses of the latter three tensor states have been used to fine-tune the free parameters of the unitary approach, i.e., the subtraction constants in evaluating the vector meson-vector meson loop functions in the dimensional regularization scheme. The branching ratios of these five dynamically generated states are found to be consistent with data. The existence of the other six states should be taken as predictions to be tested by future experiments.

Combining heavy quark spin and local hidden gauge symmetries in the dynamical generation of hidden charm baryons

C. W. X. thanks C. Hanhart, F. K. Guo, W. H. Liang, K. U. Can, A. Ozpineci, and L. L. Salcedo for helpful discussions. This work is partly supported by the Spanish Ministerio de Economia y Competitividad and European FEDER funds under Contracts No. FIS2011-28853-C02-01 and No. FIS2011-28853-C02-02, and the Generalitat Valenciana in the program Prometeo, 2009/090. We acknowledge the support of the European Community-Research Infrastructure Integrating Activity Study of Strongly Interacting Matter (Hadron Physics 3, Grant No. 283286) under the Seventh Framework Programme of the EU.

Inclusive ω photoproduction from nuclei and ω in the nuclear medium

Abstract.With the aim of extracting information on the shift of the ω mass in the nuclear medium we analyze data obtained at ELSA from where claims for evidence of a mass shift of the ω have been made. We develop a Monte Carlo simulation code which takes into account the possible reactions in the experimental set-up of (γA → π0γX) in the vicinity of the ω production region with subsequent ω → π0γ decay. We compare our results with experiment for the distribution of π0γ invariant masses and conclude that the distribution is compatible with an enlarged ω width of about 90MeV at nuclear-matter density and no shift in the mass. This change in the width would be compatible with the preliminary results obtained from the transparency ratio in the A-dependence of ω production. The discrepancy of the present conclusions with former claims of an evidence for a shift of the ω mass stems from a different choice of background which is discussed in the paper.

Hidden gauge formalism for the radiative decays of axial-vector mesons

The radiative decay of the axial-vector resonances into a pseudoscalar meson and a photon is studied using the vector meson Lagrangian obtained from the hidden gauge symmetry (HGS) formalism. The formalism is well suited to study this problem since it deals with pseudoscalar and vector mesons in a unified way, respecting chiral invariance. We show explicitly the gauge invariance of the set of diagrams that appear in the approach and evaluate the radiative decay width of the a{sub 1}(1260) and b{sub 1}(1235) axial-vector meson resonances into {pi}{gamma}. We also include the contribution of loops involving anomalous couplings and compare the results to those obtained previously within another formalism.

γγ decay of the f(0)(1370) and f(2)(1270) resonances in the hidden gauge formalism

Using recent results obtained within the hidden gauge formalism for vector mesons, in which the

The radiative decay of \psi(3770) into the predicted scalar state X(3700)

f_0(1370)

Scalar, axial-vector and tensor resonances from the rho D*, omega D* interaction in the hidden gauge formalism

and