2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/190519Partial wave amplitudes have been extracted from accurate data on pbar + p -> pi + pi by a method which incorporates the theoretical constraints of analyticity and crossing symmetry. The resulting solution gives a good fit to the annihilation data and is also consistent with the wealth of information in the crossed channel pi + N -> pi + N. The partial wave amplitudes show evidence for resonances in all partial waves with J < 6, at least one of which, a J = 0+ state, (and possibly another with J = 1-) is unlikely to have a simple quark-antiquark structure.17 pages, Revtex, 21 postscript figuresHigh Energy Physics - Phenomenologytext