High-energy dipole scattering amplitude from evolution of low-energy proton light-cone wave functions
Dumitru, A., Mäntysaari, H., & Paatelainen, R. (2023). High-energy dipole scattering amplitude from evolution of low-energy proton light-cone wave functions. Physical Review D, 107, Article 114024. https://doi.org/10.1103/PhysRevD.107.114024
Published inPhysical Review D
© Funded by SCOAP3. Published by the American Physical Society
The forward scattering amplitude of a small dipole at high energies is given in the mean field approximation by the Balitsky-Kovchegov (BK) evolution equation. It requires an initial condition N(r;x0) describing the scattering of a dipole with size r off the target that is probed at momentum fraction x0. Rather than using ad hoc parametrizations tuned to high-energy data at x≪x0, here we attempt to construct an initial scattering amplitude that is consistent with low-energy, large-x properties of the proton. We start from a nonperturbative three quark light-cone model wave function from the literature. We add O(g) corrections due to the emission of a gluon, and O(g2) virtual corrections due to the exchange of a gluon, computed in light-cone perturbation theory with exact kinematics. We provide numerical data as well as analytic parametrizations of the resulting N(r;x0) for x0=0.01–0.05. Solving the BK equation in the leading logarithmic approximation towards lower x, we obtain a fair description of the charm cross section in deeply inelastic scattering measured at HERA by fitting one parameter, the coupling constant αs≃0.2. However, without the option to tune the initial amplitude at x0, the fit of the high precision data results in χ2/Ndof=2.3 at Ndof=38, providing clear statistical evidence for the need of systematic improvement, e.g., of the photon wave function, evolution equation, and initial condition. ...
PublisherAmerican Physical Society (APS)
Publication in research information system
MetadataShow full item record
Related funder(s)Academy of Finland; European Commission
Funding program(s)Academy Research Fellow, AoF; Research costs of Academy Research Fellow, AoF
The content of the publication reflects only the author’s view. The funder is not responsible for any use that may be made of the information it contains.
Additional information about fundingThis material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, within the framework of the Saturated Glue (SURGE) Topical Theory collaboration. A. D. acknowl edges support by the DOE Office of Nuclear Physics through Grant No. DE-SC0002307, and The City University of New York for PSC-CUNY Research Grant No. 65079-00 53. This work was supported by the Academy of Finland, the Centre of Excellence in Quark Matter and Projects No. 338263 and No. 346567 (H. M.), and Projects No. 347499 and No. 353772 (R.P). H. M. is also supported under the European Union’s Horizon 2020 research and innovation program by the European Research Council (ERC, Grant Agreement No. ERC-2018-ADG 835105 YoctoLHC) and by the STRONG-2020 project (Grant Agreement No. 824093). The content of this article does not reflect the official opinion of the European Union and responsibility for the information and views expressed therein lies entirely with the authors. Computing resources from CSC–IT Center for Science in Espoo, Finland, and from the Finnish Grid and Cloud Infrastructure (persistent identifier urn:nbn:fi:research-infras-2016072533) were used in this work. ...
Showing items with similar title or keywords.
ALICE Collaboration (American Physical Society, 2020)The study of the strength and behavior of the antikaon-nucleon ((K) over bar N) interaction constitutes one of the key focuses of the strangeness sector in low-energy quantum chromodynamics (QCD). In this Letter a unique ...
Caron-Huot, Simon; Herranen, Matti (Springer, 2018)The Balitsky-Kovchegov equation describes the high-energy growth of gauge theory scattering amplitudes as well as nonlinear saturation effects which stop it. We obtain the three-loop corrections to the equation in planar ...
ALICE Collaboration (American Physical Society, 2020)In this Letter, we report the first measurement of the inelastic cross section for antideuteron-nucleus interactions at low particle momenta, covering a range of 0.3≤p<4 GeV/c. The measurement is carried out using p-Pb ...
Uncertainties on the determination of the strong coupling αs from the energy evolution of jet fragmentation functions at low z d'Enterria, David; Perez-Ramos, Redamy (Elsevier BV, 2016)The QCD coupling αs is determined at NLO*+NMLLA accuracy from the comparison of experimental jet data to theoretical predictions of the energy-evolution of the parton-to-hadron fragmentation function moments (multiplicity, peak, ...
Production of pions, kaons, and protons as a function of the relative transverse activity classifier in pp collisions at √s = 13 TeV ALICE Collaboration (Springer, 2023)