2 papers
hep-ph2005
Mass and width of the lowest resonance in QCD
Irinel Caprini, Gilberto Colangelo, Heinrich Leutwyler
We demonstrate that near the threshold, the pi pi scattering amplitude contains a pole with the quantum numbers of the vacuum - commonly referred to as the sigma - and determine it…
hep-ph2003
On the precision of the theoretical predictions for pi pi scattering
I. Caprini, G. Colangelo, J. Gasser +1
In a recent paper, Pelaez and Yndurain evaluate some of the low energy observables of pi pi scattering and obtain flat disagreement with our earlier results. The authors work with…