Details

Autor(en) / Beteiligte

• Xu, Y.-Z.
• Binosi, D.
• Cui, Z.-F.
• Li, B.-L.
• Roberts, C. D.
• Xu, S.-S.
• Zong, H.-S.

Titel

Elastic electromagnetic form factors of vector mesons

Ist Teil von

• Physical review. D, 2019-12, Vol.100 (11), p.1, Article 114038

Ort / Verlag

College Park: American Physical Society

Erscheinungsjahr

2019

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• A symmetry-preserving approach to the two valence-body continuum bound-state problem is used to calculate the elastic electromagnetic form factors of the ρ-meson and subsequently to study the evolution of vector-meson form factors with current-quark mass. To facilitate a range of additional comparisons, K* form factors are also computed. The analysis reveals that vector mesons are larger than pseudoscalar mesons; composite vector mesons are nonspherical, with magnetic and quadrupole moments that deviate ∼30% from point-particle values; in many ways, vector-meson properties are as much influenced by emergent mass as those of pseudoscalars; and vector-meson electric form factors possess a zero at spacelike momentum transfer. Qualitative similarities between the electric form factors of the ρ and the proton, GEp, are used to argue that the character of emergent mass in the Standard Model can force a zero in GEp. Moreover, the existence of a zero in vector-meson electric form factors entails that a single-pole vector-meson dominance model can only be of limited use in estimating properties of off-shell vector mesons, providing poor guidance for systems in which the Higgs mechanism of mass generation is dominant.