Unitarisation of the hard pomeron and black-disk limit at the LHC

Abstract

Recent models of soft diffraction include a hard pomeron pole besides the usual soft term. Such models violate the black-disk limit around Tevatron energies, so that they need to be supplemented by a unitarisation scheme. Several such schemes are considered in this letter, where we show that they lead to a large uncertainty at the LHC. We also examine the impact of unitarisation on various small-t observables, the slope in t of the elastic cross section, or the ratio of the real to imaginary parts of the scattering amplitude, leading to the conclusion that the existence of a hard pomeron in soft scattering may be confirmed by LHC data.

arXiv comment15 pages, 12 figures, latex

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Cited by in corpus (13)

• Elastic scattering of hadrons
• Forward Physics at the LHC; Elastic Scattering
• New analytic unitarization schemes
• How precisely will the total cross section be measured at the LHC?
• Hard and soft pomerons in elastic nucleon scattering
• Total photoproduction cross-section at very high energy
• Test of Universal Rise of Hadronic Total Cross Sections based on pi p, Kp and pbar p,pp Scatterings
• Soft diffraction within the QCD color dipole picture
• Minijets, soft gluon resummation and photon cross-sections
• QCD Mini-jet contribution to the total cross section
• Large rapidity gaps survival probabilities at LHC
• The spin-flip amplitude in the impact-parameter representation
• Total Cross-sections at very high energies: from protons to photons