For excited nucleon states $N^{*}$ of arbitrary spin coupling to nucleon (N) and meson $\mathrm{}\left(M\right),$ we propose a Lorentz covariant orbital-spin $\mathrm{}(L-S)\mathrm{}$ scheme for the effective $N^{*}\mathrm{NM}$ 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 formulas are given for $N^{*}\to N\pi ,$ $N^{*}\to N\omega ,$ and $\overrightarrow{\psi }{N}^{*}\overline{N}$ processes which are under current experimental studies.

• Received 11 October 2002

DOI:https://doi.org/10.1103/PhysRevC.67.015204