Work

Transition from a relativistic constituent-quark model to the quantum-chromodynamical asymptotics: A quantitative description of the pion electromagnetic form factor at intermediate values of the momentum transfer

Year: 2013

Type: article

Abstract: We adopt a nonperturbative relativistic constituent-quark model for the $\ensuremath{\pi}$-meson electromagnetic form factor, which has successfully predicted experimental results, and supplement it with the effective momentum-dependent quark mass to study quantitatively the transition to the perturbative QCD asymptotics. The required asymptotical behavior (including both the ${Q}^{\ensuremath{-}2}$ falloff and the correct coefficient) settles down automatically when the quark mass is switched off; however, the present experimental data on the form factor suggest that this cannot happen at the values of the momentum transfer below $\ensuremath{\sim}10\text{ }\text{ }{\mathrm{GeV}}^{2}$. The effective constituent-quark mass below this scale acquires substantial nonperturbative contributions.

Source: Physical review. D. Particles, fields, gravitation, and cosmology/Physical review. D. Particles and fields

DOI: 10.1103/physrevd.88.093005

Authors: S. V. Troitsky, V. E. Troitsky

Institutions: Institute for Nuclear Research, Lomonosov Moscow State University, Skobeltsyn Institute of Nuclear Physics, Lomonosov Moscow State University

Language: English

Topic: Quantum Chromodynamics and Particle Interactions

Subfield: Nuclear and High Energy Physics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: green

Funders: CERN, Russian Foundation for Basic Research

Awards: G3068352079, G5364595252, G6409582158, G6919412579