2019/06/30 by B. I. Ermolaev, S. I. Troyan
Physics and Astronomy · #Amplitude #Compton scattering #DGLAP #Factorization #Hadron #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Perturbative QCD #Photon #Quantum Chromodynamics and Particle Interactions #Quantum chromodynamics #hep-ph
paper · pdf · doi:10.1140/epjc/s10052-020-7630-6
published as Published in: Eur. Phys.J.C 20(2020)98 · 17 pp, 2 figures, multiple drawbacks of the previous version are corrected
openalex created_date 2019/06/27 · openalex publication_date 2020/02/01 · arxiv created 2021/11/12 · arxiv updated 2021/11/15 · openalex updated_date 2026/08/05
Abstract We study amplitudes of the inclusive photon induced high-energy processes: elastic Compton scattering off hadrons and photoproduction. Although description of these amplitudes includes both non-perturbative and perturbative contributions, QCD factorization makes possible to study them separately. Throughout the present paper we focus on the perturbative amplitudes and study such amplitudes in all available in the literature forms of QCD factorization: Collinear, KT <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>K</mml:mi><mml:mi>T</mml:mi></mml:msub></mml:math> and Basic. As a result, we obtain expressions for the perturbative Compton amplitudes, which can be used at arbitrary x and Q2 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msup><mml:mi>Q</mml:mi><mml:mn>2</mml:mn></mml:msup></mml:math> in any form of QCD factorization. Putting Q2 = 0 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mi>Q</mml:mi><mml:mn>2</mml:mn></mml:msup><mml:mo>=</mml:mo><mml:mn>0</mml:mn></mml:mrow></mml:math> in those expressions allows us to obtain expressions for the perturbative components of the photoproduction amplitudes. The small- x asymptotics of the Compton amplitudes in any form of QCD factorization are of the Regge type, with the Reggeon being a double-logarithmic (non-BFKL) contribution to Pomeron.