High-energy dynamics of QCD: Theoretical and phenomenological results

This work investigates the behavior of hadronic matter in the high-energy Regge-Gribov (semi-hard) regime of Quantum Chromodynamics (QCD), accessible through current and future colliders such as the LHC, EIC, and FCC. Central to the analysis is the Balitsky-Fadin-Kuraev-Lipatov (BFKL) formalism, with detailed treatment of the BFKL equation in both leading and next-to-leading logarithmic approximations. A major focus is placed on the computation of real next-to-leading order (NLO) corrections to the Higgs boson impact factor, incorporating finite top-quark mass effects. These corrections are essential for improving precision in Higgs production processes at large rapidity separations. The study also explores the semi-inclusive production of exotic tetraquark states, employing a hybrid framework that combines collinear and BFKL dynamics within a variable-flavor number scheme. Updated fragmentation functions for bottomonium-like states are provided, offering improved predictions at 14 TeV and 100 TeV. Additionally, the work addresses diffractive di-hadron production in the small-x saturation regime using the Color Glass Condensate (CGC) formalism, presenting preliminary leading-order analytical results.