Affiliation:
1. Institute of Nuclear Physics PAN, PL-31-342 Cracow, Poland
2. University of Rzeszów, PL-35-959 Rzeszów, Poland
Abstract
We report on a detailed investigation of four-body pp → ppπ+π- and [Formula: see text] reactions which constitute an irreducible background to three-body processes pp → ppM, where M is a broad resonance in the π+π- channel, e.g. M = σ, ρ0, f0(980), f2(1275), f0(1500). We include double-diffractive contribution (both pomeron and reggeon exchanges) as well as the pion-pion rescattering contributions. The first process dominates at higher energies and small pion-pion invariant masses while the second becomes important at lower energies and higher pion-pion invariant masses. We compare our results with the experimental data. We make predictions for future experiments at PANDA, RHIC, Tevatron and LHC energies. The two-dimensional distribution in rapidity space of pions (yπ+, yπ-) is particularly interesting. The higher the incident energy, the higher preference for the same-hemisphere emission of pions. The processes considered constitute a sizeable contribution to the total nucleon-nucleon cross section as well as to pion inclusive cross section.
Publisher
World Scientific Pub Co Pte Lt
Subject
Astronomy and Astrophysics,Nuclear and High Energy Physics,Atomic and Molecular Physics, and Optics