Preasymptotic nature of hadron scattering vs small-x HERA data

Abstract

We emphasize that recently observed regularities in hadron interactions and deep-inelastic scattering are of preasymptotic nature and it is impossible to make conclusions on the true asymptotic behavior of observables without unitarization procedure. Unitarization is important and changes scattering picture drastically.

Effects of Reflective Scattering in Nuclear Collisions

“…We can approximate p R (s) by the value of |S(s, b = 0)| 2 which tends to unity at s → ∞. It should be noted that the value √ s R ≃ 2 T eV [11]. Below this energy there is no reflective scattering, α(s) = 0 at s ≤ s R , and therefore corrections to the hadron density are absent.…”

Beyond the black-disk limit: from shadow to antishadow scattering mode

“…Numerical estimates [19] show that the ratio σ el (s)/σ tot (s) bocomes close to the asymptotic value 1 at extremely high energies √ s = 500…”

“…We consider for illustration the unitarized chiral quark model (section 4). Fit to the total hp cross-sections gives small values for the parameters g and α ( g, α ≪ 1) [19]. It means that at s ≪ s 0 the second term in the square brackets in Eqs.…”

“…(21) and (22) is small and we can expand over it. The numerical value of s 0 is determined by the equation |U(s, 0)| = 1 and is [19] √ s 0 ≃ 2 TeV. At this energy the amplitude has the value |f (s 0 , 0)| = 1/2.…”

“…The region of energies and impact parameters corresponding to the antishadow scattering mode is determined by the conditions Imf (s, b) > 1/2 and η(s, b) < 1/4. The quantitative analysis of the experimental data [19] gives the threshold value of energy:…”