A unitarity analysis on the I=0 d wave pi pi scattering amplitude

作者：Wang JJ^*; Zhou ZY; Zheng HQ

来源：The Journal of High Energy Physics, 2005, (12).

• chiral Lagrangians

We study I=0 d wave pi pi scattering phase shift using a proper unitarization approach. It is verified that the f(2)( 1270) resonance corresponds to a twin pole structure: one on the second sheet, another one on the third sheet. Also we find fair agreement on f(2)(1270) pole's mass and width between our results and the PDG values. Besides, our analysis reveals the existence of a virtual state in this channel. Its pole location is determined by fitting experimental data and it is found to be in good agreement with the prediction from chiral perturbation theory. Our analysis demonstrates that partial wave amplitudes calculated in chiral perturbation theory are reliable in the small vertical bar s vertical bar region, contrary to some unitarization models.

• 出版日期2005-12
• 单位北京大学