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Some mass relations for mesons and baryons in Regge phenomenology

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 نشر من قبل Ke-Wei Wei
 تاريخ النشر 2008
  مجال البحث
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In the quasilinear Regge trajectory ansatz, some useful linear mass inequalities, quadratic mass inequalities and quadratic mass equalities are derived for mesons and baryons. Based on these relations, mass ranges of some mesons and baryons are given. The masses of bc-bar and ss-bar belonging to the pseudoscalar, vector and tensor meson multiplets are also extracted. The J^P of the baryon Xi_cc(3520) is assigned to be 1/2^+. The numerical values for Regge slopes and intercepts of the 1/2^+ and 3/2^+ SU(4) baryon trajectories are extracted and the masses of the orbital excited baryons lying on the 1/2^+ and 3/2^+ trajectories are estimated. The J^P assignments of baryons Xi_c(2980), Xi_c(3055), Xi_c(3077) and Xi_c(3123) are discussed. The predictions are in reasonable agreement with the existing experimental data and those suggested in many other different approaches. The mass relations and the predictions may be useful for the discovery of the unobserved meson and baryon states and the J^P assignment of these states.

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