New Solutions for Scalar-Isoscalar pi-pi Phase Shifts
Abstract
The scalar-isoscalar pi-pi phase shifts are calculated in the pi-pi energy range from 600 MeV to 1600 MeV. We use results of the CERN-Cracow-Munich collaboration for the reaction pi^- p --> pi^+ pi^- n on a transversely polarized target at 17.2 GeV/c pi^- momentum. Energy-independent separation of the S-wave pseudoscalar amplitude (pi exchange) from the pseudovector amplitude (a_1 exchange) is carried out. Below the KK threshold we find two solutions for the pi-pi phase shifts, for which the phases increase slower with the effective pi-pi mass than the P-wave phases ("flat" solutions) and two solutions for which the phases increase faster than the P-wave phases ("steep" solutions). Above 1420 MeV both sets of phase shifts increase with energy faster than in the experiment on an unpolarized target. This fact can be related to a presence of the scalar resonance f_0(1500).
Cite
@article{arxiv.hep-ph/9712336,
title = {New Solutions for Scalar-Isoscalar pi-pi Phase Shifts},
author = {R. Kaminski and L. Lesniak and K. Rybicki},
journal= {arXiv preprint arXiv:hep-ph/9712336},
year = {2016}
}
Comments
5 pages, 2 figures. Talk given at 7th International Conference on Hadron Spectroscopy (Hadron 97), Upton, NY, 25-30 Aug 1997