Hadronic vacuum polarization and light-by-light scattering in representative infrared-improved soft-wall holographic QCD models
- 1Hunan University
Abstract
We investigate the hadronic contributions to the anomalous magnetic moment of the muon aμ in three representative infrared-improved soft-wall anti-de Sitter (AdS)/quantum chromodynamics (QCD) models, focusing on the leading-order hadronic vacuum polarization (LO-HVP) and hadronic light-by-light (HLbL) contributions. The model parameters are fixed by the ground-state ρ-meson mass, pion mass, and pion decay constant, with the low-lying excited spectrum used as an additional phenomenological constraint. We find that the LO-HVP contribution remains below dispersive determinations, mainly because the ρ-meson decay constant is underestimated. In the HLbL sector, the standard Chern–Simons term gives well-defined ground-state pseudoscalar-pole contributions but leads to divergent excited-state sums in soft-wall models. We therefore also adopt a scalar-extended Chern–Simons term motivated by brane–antibrane construction, which provides infrared suppression and allows finite estimates for pseudoscalar excitations and axial-vector mesons. The resulting HLbL predictions are internally convergent but still quantitatively model-dependent, showing that further refinement of the infrared completion and short-distance constraints is required.
Related
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- Electromagnetic isospin breaking in hadronic vacuum polarization within a VMD model
- Hadronic light-by-light scattering in AdS/QCD and the muon g−2: tensor meson contributions
- Hadronic scattering in (1+1)D SU(2) lattice gauge theory from tensor networks
- Higher-twist hadronic tensor in deep inelastic scattering with massive quarks
BibTeX
@article{shen2026hadronic,
title = {{Hadronic vacuum polarization and light-by-light scattering in representative infrared-improved soft-wall holographic QCD models}},
author = {Jin-Yang Shen and Wen-Yuan Peng and Ling-Yun Dai and Zhen Fang},
journal = {The European Physical Journal C},
year = {2026},
month = nov,
doi = {10.1140/epjc/s10052-026-16431-3},
url = {https://link.springer.com/article/10.1140/epjc/s10052-026-16431-3},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Hadronic vacuum polarization and light-by-light scattering in representative infrared-improved soft-wall holographic QCD models
AU - Jin-Yang Shen
AU - Wen-Yuan Peng
AU - Ling-Yun Dai
AU - Zhen Fang
PY - 2026
DA - 2026/11/03
JO - The European Physical Journal C
DO - 10.1140/epjc/s10052-026-16431-3
UR - https://link.springer.com/article/10.1140/epjc/s10052-026-16431-3
AB - We investigate the hadronic contributions to the anomalous magnetic moment of the muon a_μ in three representative infrared-improved soft-wall anti-de Sitter (AdS)/quantum chromodynamics (QCD) models, focusing on the leading-order hadronic vacuum polarization (LO-HVP) and hadronic light-by-light (HLbL) contributions. The model parameters are fixed by the ground-state ρ-meson mass, pion mass, and pion decay constant, with the low-lying excited spectrum used as an additional phenomenological constraint. We find that the LO-HVP contribution remains below dispersive determinations, mainly because the ρ-meson decay constant is underestimated. In the HLbL sector, the standard Chern–Simons term gives well-defined ground-state pseudoscalar-pole contributions but leads to divergent excited-state sums in soft-wall models. We therefore also adopt a scalar-extended Chern–Simons term motivated by brane–antibrane construction, which provides infrared suppression and allows finite estimates for pseudoscalar excitations and axial-vector mesons. The resulting HLbL predictions are internally convergent but still quantitatively model-dependent, showing that further refinement of the infrared completion and short-distance constraints is required.
SN - 1434-6052
ER -