Resonances of arbitrary multiplicity
The constraints of unitarity on an amplitude containing J degenerate resonances are solved, and several parametrizations of the solution are given. In one solution, the unitary amplitude is obtained from the narrow-width limit. Forms suitable for other theoretical applications and for phenomenology are included. The wide variety of possible cross sections and Argand diagrams for the general case are discussed, and examples of the tripole are shown. The well-known results for the dipole are rederived without effort. © 1971 The American Physical Society.