A lower bound of 135 MeV for the width of the \xi meson is obtained from analyzing the pp and pbar-p interactions by use of Regge theory. The pp data exclude a narrow \xi as the latter would lead to total pbar-p cross sections far exceeding the measured ones. The broad width explains why the \xi may not be seen in pbarp-p experiments.
Cite
@article{arxiv.hep-ph/0201237,
title = {The width of the \xi(2230) meson},
author = {L. C. Liu},
journal= {arXiv preprint arXiv:hep-ph/0201237},
year = {2009}
}