2013/06/28 by Lebiedowicz, Piotr, Szczurek, Antoni
#FOS: Physical sciences #High Energy Physics - Phenomenology (hep-ph) #Nuclear Theory (nucl-th)
paper · doi:10.48550/arxiv.1306.6823
We present a study of exclusive production of π0 meson in proton-proton collisions at high energies. Both diffractive bremsstrahlung (Drell-Hiida-Deck type model), photon-photon, photon-omega and photon-odderon exchange mechanisms are included in the calculation. The π0-bremsstrahlung contribution dominates at large (forward, backward) pion rapidities and contributes at small π0 p invariant mass and could be therefore misinterpreted as the Roper resonance N*(1440). Large cross sections of the order of mb are predicted. We predict strong dependence of the slope in t (squared four-momentum transfer between ingoing and outgoing proton) on the mass of the supplementary excited π0 p system. At high energy and midrapidity, the photon-photon contribution dominates over the diffractive components, however, the corresponding cross section is rather small. The photon-odderon and odderon-photon contributions are included in addition and first estimates (upper limits) of their contributions are presented. We suggest a search for the odderon contribution at midrapidity and at p⊥,π0 ∼ 0.5 GeV. Our predictions are ready for verification at LHC. The bremsstrahlung mechanisms discussed here contribute also to the pp → p(n π+) reaction. Both channels give a sizable contribution to the low-mass single diffractive cross section and must be included in extrapolating the measured experimental single diffractive cross section.