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Register a new userBaryon Production at LHC Experiments: Average pt of Hyperons vs. Energy
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Authors
Olga I. Piskounova
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This paper examines the transverse momentum spectra of baryons in the multi-particle production at modern colliders using Quark-Gluon String Model (QGSM). It discusses 1) the difference in Lambda^0 hyperon spectra at antiproton-proton vs. proton-proton reactions; 2) the growth of average transverse momenta of Lambda hyperon with proton-proton collision energies and 3) the dependence of average p_t on the masses of mesons and baryons at the LHC energy 7 TeV. This analysis of baryon spectra led to the following conclusions. First, the fragmentation of antidiquark-diquark side of the pomeron diagram makes the major contribution to baryon production spectra in the asymmetric antiproton-proton reaction. Second, the average p_ts of hyperons steadily grow with energy on the range from 53 GeV to 7 TeV. Since no dramatic changes were seen in the characteristics of baryon production, the hadroproduction processes do not cause the knee in the cosmic ray proton spectra at the energies between Tevatron and LHC.
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This paper examines the transverse momentum spectra of hadrons in the multiparticle production at LHC in the framework of the Quark-Gluon String Model (QGSM). It discusses the dependence of average pt on the masses of mesons and baryons at the LHC energy 7 TeV. The QGSM description of the experimental spectra of various hadrons led to the number of conclusions. I. The average transverse momenta of baryons and mesons are growing with the hadron mass and for beauty hadrons, they are almost equal to the mass. II. By the product of research, a regularity has been detected in the mass gaps between hadron generations. This hypothesis suggests some hidden symmetrical (neither-meson-nor-baryon) neutral hadron states with the masses: 0.251,0.682,1.85,5.04,13.7,37.2,101.,275.,748.... GeV, which is produced by geometrical progression with the mass factor of order delta(ln M)=1. III. The baryon-meson symmetry seems broken until the mass of beauty hadrons, then the hidden states should be more and more stable with the growth of the mass, so the suggested sequence of hadronic states is a proper candidate for the Dark Matter that, you know, contributes the valuable part to the mass of Universe. The growing average transverse momenta are extrapolated with a similar function, as for energy dependence of average baryon pt, < pt > ~ M**0.1.
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