Exclusive Central π⁺π⁻ Production in Proton Antiproton Collisions at the CDF

¹ Forschungszentrum Jülich, 52425 Jülich Germany
² University of Cologne, 50937 Cologne Germany

^a e-mail: m.zurek@fz-juelich.de

Published online: 4 July 2016

Abstract

Exclusive π⁺π⁻ production in proton-antiproton collisions at √s = 0.9 and 1.96 TeV in the Collider Detector at Fermilab has been measured. We select events with two particles with opposite charge in pseudorapidity region −1.3 < η < 1.3 with no other particles detected in −5.9 < η < 5.9. Particles are assumed to be pions. The π⁺π⁻ system is required to have rapidity −1.0 < y < 1.0. The data are expected to be dominated by the double pomeron exchange mechanism. Therefore, the quantum numbers of the central state are constrained. The data extend up to dipion mass M(π⁺π⁻) = 5000 MeV/c². Resonance structures consistent with f₀ and f₂(1270) mesons are visible. The results are valuable for light hadron spectroscopy and for providing information about the nature of the pomeron in a region between non-perturbative and perturbative quantum chromodynamics.