On gauge invariance of transverse momentum dependent distributions at small x

Abstract

The interplay between the small x limit of QCD amplitudes and QCD factorization at moderate x has been studied extensively in recent years. It was finally shown that semiclassical formulations of small x physics can have the form of an infinite twist framework involving Transverse Momentum Dependent (TMD) distributions in the eikonal limit. In this work, we demonstrate that small x distributions can be formulated in terms of transverse gauge links. This allows in particular for direct and efficient decompositions of observables into subamplitudes involving gauge invariant sub-operators which span parton distributions.

21 pages, 5 figures

References in corpus (8)

• The Color Glass Condensate
• Universality of Unintegrated Gluon Distributions at small x
• kt-factorization for Hard Processes in Nuclei
• Forward di-jet production in p+Pb collisions in the small-x improved TMD factorization framework
• Transverse-momentum-dependent gluon distributions from JIMWLK evolution
• Dipole factorization for DIS at NLO: Combining the $q\bar{q}$ and $q\bar{q}g$ contributions
• Azimuthal asymmetries for quark pair production in pA collisions
• Interplay of the CGC and TMD frameworks to all orders in kinematic twist

Cited by in corpus (11)

• Mining for Gluon Saturation at Colliders
• Back-to-back inclusive dijets in DIS at small $x$: Sudakov suppression and gluon saturation at NLO
• The importance of kinematic twists and genuine saturation effects in dijet production at the Electron-Ion Collider
• Quark and scalar propagators at next-to-eikonal accuracy in the CGC through a dynamical background gluon field
• Low-$x$ improved TMD approach to the lepto- and hadroproduction of a heavy-quark pair
• Gluon-mediated inclusive Deep Inelastic Scattering from Regge to Bjorken kinematics
• Incoherent diffractive dijet production in electron DIS off nuclei at high energy
• Quark TMDs from back-to-back dijet production at forward rapidities in pA collisions beyond eikonal accuracy in the CGC
• Dijet impact factor in DIS at next-to-leading order in the Color Glass Condensate
• Dijet photoproduction at low $x$ at next-to-leading order and its back-to-back limit
• Coherent energy loss effects in dihadron azimuthal angular correlations in Deep Inelastic Scattering at small $x$