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arXiv · 1405.4398

Average Transverse Momenta in Hyperon Production at p-p Collider Experiments

Abstract

The previously publicated analysis of transverse momentum spectra of $\Lambda^0$ hyperons from LHC experiments (ALICE, ATLAS, CMS)in the comparison with earlier experiments was reconsidered with correct spectra from STAR collaboration. The LHC data at $\sqrt{s}$ = 0.9 and 7 TeV and the data of proton-proton experiments of lower energies were fitted with the universal formula that includes the energy dependent slope as the main parameter. The dependence of average transverse momenta on $\sqrt{s}$ has been obtained with the help of this formula. The asymptotics of the energy dependence of average Pt shows the behavior $ ~ s^{0.05}$, that was not expected in early description of hadron transverse momentum in the framework of Quark-Gluon String Model. The previous important conclusion about spectra of cosmic rays was not changed: the long debated "knee" in the cosmic proton spectra at $E_p= (2,5 - 4)*10^{15}$ eV in laboratory system can not be considered any more as the result of dramatic changes in the dynamics of baryon hadroproduction. The reason of the steadily growing of average Pt seems situated outside the predictive power of QGSM. Nevertheless the average transverse momentum can reach a constant value with higher energies that has been predicted in our model long ago.

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Olga Piskounova. 2014-05-17. Average Transverse Momenta in Hyperon Production at p-p Collider Experiments. https://doi.org/10.1088/1742-6596/607/1/012012

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