Diffractive Processes at Next-to-Leading Order in the Dipole Picture

TL;DR

This thesis advances the theoretical understanding of diffractive processes at NLO in the dipole picture, demonstrating the universality of the dipole-target scattering amplitude across various DIS processes and providing analytical calculations for vector meson production.

Contribution

It provides the first comprehensive NLO calculations for diffractive processes in the dipole picture, emphasizing the universality of the dipole-target scattering amplitude and including relativistic corrections.

Findings

Universality of dipole-target scattering amplitude at NLO across processes

Analytical NLO calculations for vector meson production and inclusive diffraction

Cancellation of divergences in NLO corrections to final states

Abstract

In this thesis, we calculate diffractive processes at next-to-leading order (NLO) in the high-energy limit, with an emphasis on exclusive vector meson production and inclusive diffraction in deep inelastic scattering (DIS). Calculations in the high-energy limit can be done using the dipole picture, the basics of which are briefly reviewed. This includes using the color-glass condensate effective field theory to describe the nonperturbative dipole-target scattering amplitude which appears in practically all calculations in the dipole picture. The universality of the dipole-target scattering amplitude at NLO is shown numerically, in the sense that the same dipole-target scattering amplitude can be used to describe the data in both massless and massive quark production in inclusive DIS, and also in diffractive processes where exclusive vector meson production is considered. The analytical NLO calculations of exclusive vector meson production and inclusive diffraction in DIS are also explained. Exclusive vector meson production is calculated in the nonrelativistic limit for heavy mesons and the limit of large photon virtuality for light mesons. Also, the importance of including relativistic corrections to the heavy vector meson wave function in exclusive vector meson production is considered. For inclusive diffraction in DIS, we focus on the NLO corrections to the final state and show how the divergences cancel.