Lorentz covariant orbital-spin scheme for the effectiveN*NMcouplings

Abstract

For excited nucleon states N * of arbitrary spin coupling to nucleon (N) and meson (M), we propose a Lorentz covariant orbital-spin (L-S) scheme for the effective N * N M couplings. To be used for the partial wave analysis of various N * production and decay processes, it combines merits of two conventional schemes, i.e., covariant effective Lagrangian approach and multipole analysis with amplitudes expanded according to angular momentum L. As examples, explicit formulae are given for N * → N π, N * → N ω and ψ → N * N processes which are under current experimental studies.

Role of the resonance in the reaction

“…[23] any attempt to include the ρ-meson exchange worsens the agreement with experiments of pp → n∆ ++ reactions. A Lorentz covariant orbital-spin(L-S) scheme [26] are used for the effective ∆πN, N * σN, and N * πN vertices.…”

Phenomenological study on the reactions

“…Other resonances give negligible contributions so we can safely ignore them. The effective Lagrangians for the relevant resonance couplings are [15,16],…”

Role of theN*(2080)inpp→pK+Λ(Xie1, Liu2 2013Phys. Rev. C406610View full textAdd to dashboardCite

“…1, we use the interaction Lagrangian densities as in Refs. [15,[22][23][24][25][26][27][28][29][30],…”