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Register a new userThe Difference Between Hyperon Transverse Momentum Distributions in Proton-Proton and Proton-Antiproton Collisions
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O. I. Piskounova
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The analysis of data on hyperon transverse momentum distributions, dN/dPt, that were gathered from various experiments (ISR, STAR, UA1, UA5 and CDF) reveals an important difference in the dynamics of multiparticle production in proton-proton vs. antiproton-proton collisions in the region of transverse momenta 0.3 GeV/c < Pt < 3 GeV/c. Hyperons produced with proton beams display the sharp exponential slope at low Pt, while spectra prodused with antiproton beam dont. Since LHC experiments have proton projectiles, the spectra of baryon production should seem softer in comparison to expectations, because the Monte Carlo simulations were based on the Tevatron antiproton-proton data. From the point of view of Quark-Gluon String Model, the most important contribution into the particle production spectra goes from antidiquark-diquark string fragmentation that exists only in the topological diagram for antiproton-proton collisions and is a very interesting object for investigation even at lower energies. This study may have an impact not only on interpretation of LHC results, but also on the cosmic ray physics and astrophysics, where the baryon contribution into matter-antimatter asymmetry is being studied.
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