Positivity and unitarity constraints on dipole gluon distributions

Abstract

In the high-energy domain, gluon transverse-momentum dependent distributions in nuclei obey constraints coming from positivity and unitarity of the colorless QCD dipole distributions through Fourier-Bessel transformations. Using mathematical properties of Fourier-positive functions, we investigate the nature of these constraints which apply to dipole model building and formulation

Comments: 11 pages, 2 figures, Dedicated to Andrzej Bialas in honor of his 80th birthday