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arXiv · 1404.4142

Torus or black disk?

I. M. Dremin
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Abstract

We show that the interaction region of colliding protons looks completely absorptive (black) at the impact parameters up to 0.4 - 0.5 fm at the LHC energy 7 TeV. It is governed by the ratio of the elastic diffraction peak slope to the total cross section. The corresponding parameter is approximately equal to 1 at the LHC. The behavior of this ratio at higher energies will show if this region will evolve to the black disk or to the black torus. Recent fits at 7 TeV can not distinguish between these possibilities within the limits of experimental indefiniteness and of extrapolations in the regions of unmeasured transferred momenta.

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I. M. Dremin. 2014-04-16. Torus or black disk?. https://doi.org/10.3103/s1068335615010066

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