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arXiv · 0708.3636

Evidences for two scales in hadrons

B. Z. Kopeliovich·I. K. Potashnikova·B. Povh·Ivan Schmidt
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Abstract

Some unusual features observed in hadronic collisions at high energies can be understood assuming that gluons in hadrons are located within small spots occupying only about 10% of the hadron's area. Such a conjecture about the presence of two scales in hadrons helps to explain: why diffractive gluon radiation so much suppressed; why the triple-Pomeron coupling shows no t-dependence; why total hadronic cross sections rise with energy so slowly; why diffraction cone shrinks so slowly, and why $α^\prime_P\llα^\prime_R$; why the transition from hard to soft regimes in the structure functions occurs at rather large $Q^2$; why the observed Cronin effect at collider energies is so weak; why hard reactions sensitive to primordial parton motion (direct photon, Drell-Yan dileptons, heavy flavors, back-to-back di-hadrons, seagull effect, etc.) demand such a large transverse momenta of the projectile partons, which is not explained by NLO calculations; why the onset of nuclear shadowing for gluons is so much delayed compared to quarks, and why shadowing is so weak.

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B. Z. Kopeliovich, I. K. Potashnikova, B. Povh, Ivan Schmidt. 2007-08-27. Evidences for two scales in hadrons. https://doi.org/10.1103/physrevd.76.094020

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