2003/08/01 by Ahmad Idilbi, Xiangdong Ji, Jian-Ping Ma
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.69.014006
published as Phys.Rev. D69 (2004) 014006 · 9 pages, two figures
arxiv created 2003/08/01 · openalex publication_date 2004/01/26 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present a leading-order PQCD factorization formula for the helicity-flip \stackrel\ensuremath→\ensuremathΔN\ensuremathγ* matrix element G0 (Coulomb quadrupole amplitude C2), taking into account the transverse momenta of the quarks and the contribution from the gluons. In the large Q2 limit, its scaling behavior acquires a double-logarithmic correction log2(Q2/\ensuremathΛ2) compared with the standard scaling analysis, due to the contribution from the orbital motion of the small-x partons. Based on this and on the latest JLab experimental results of the C2\ensuremath-M1 ratio RSM at Q2=3--4GeV2, we make a phenomenological prediction for the latter at higher values of Q2.