Interpretation of an "edge" in proton-proton scattering

Abstract

A study of proton-proton collisions at very high energy has revealed a "black disk," whose radius grows with the logarithm of the center-of-mass energy, surrounded by an edge of approximately constant width 1 fm. We interpret this behavior as the maximum length of a QCD string connecting the color triplet and antitriplet components of the proton, and propose further tests of this explanation.

Comments: 4 pages, 1 figure, to be submitted to Phys. Rev. D. Some references and acknowledgments added