[en] Doubly differential continuum cross sections from the ⁹⁰Zr(p, n) ⁹⁰Nb reaction have been analyzed via a multipole-decomposition technique. No quasi-free charge-exchange background has been subtracted, following the assumption that the observed cross sections are primarily due to one-step charge-exchange leading to 1p-1h states of all multipolarities to all excitations. The theoretical shapes of the differential cross sections for each J^π multipole have been taken from random-phase approximation (RPA) - distorted-wave impulse approximation (DWIA) calculations. the experimental dσ / dΩ for each 1 MeV excitation-energy bin have been decomposed into different multipole components by a least squares fit. This RPA-based analysis should determine the J^π = 1⁺ cross sections with different, and also fewer, assumptions than usual for describing the underlying background. It can be of general importance in determining the extent of possible quenching of Gamow-Teller (GT) strength. The present decomposition accounts for all the theoretically predicted GT strength. The purpose of the present report is to illustrate an analysis based on RPA-DWIA shapes rather than to present final-decomposition results