Date of Award
Summer 2025
Document Type
Dissertation
Degree Name
Doctor of Philosophy (PhD)
Department
Physics
Program/Concentration
Physics
Committee Director
Ted C. Rogers
Committee Member
Raúl A. Briceño
Committee Member
Alexander Godunov
Committee Member
Yaohang Li
Committee Member
Yuan Zhang
Abstract
The main purpose of this thesis is to investigate the theoretical foundations of the factorization theorems that involve transverse quark and gluon momentum distributions, and to better understand the interface between foundational questions and phenomenological applications. Many of these applications involve using transverse parton momentum dependent (TMD) correlation functions as tools for probing the complex nonperturbative structures of the hadrons.
We first introduce the concepts of collinear and TMD factorization in a toy-model theory and, by leveraging the comparative simplicity of such a model, we test the range of validity and limitations of the factorization approach. At the same time, we introduce the conventional approaches that are adopted for the phenomenological extractions of the TMD distributions, and catalog the advantages and disadvantages.
Following the general theoretical framework of factorization, we then develop a different approach to TMD phenomenology that is able to systematically integrate the perturbative and nonperturbative information in parametrizations of TMD distributions, while being completely consistent with their operator definitions and the predictions of QCD, including their nontrivial evolution. The name Hadron Structure Oriented approach, or HSO, is coined in order to emphasize the central role of the nonperturbative nature of QCD and its relation to the partonic structure of hadrons.
Finally, we provide a first phenomenological implementation of the HSO approach by extracting TMD distributions relying on low-to-moderate energy Drell-Yan data. The quality and robustness of the results are then compared against higher energy processes like high-Q2 Z0 boson production. Our analysis demonstrates the feasibility of this novel approach and points the way toward the improvements it can achieve in future applications.
Rights
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DOI
10.25777/8ken-sa63
ISBN
9798293842797
Recommended Citation
Rainaldi, Tommaso.
"Unraveling Nonperturbative QCD with Transverse Momentum Hadronic Structures"
(2025). Doctor of Philosophy (PhD), Dissertation, Physics, Old Dominion University, DOI: 10.25777/8ken-sa63
https://digitalcommons.odu.edu/physics_etds/218
ORCID
0000-0002-8342-6765