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  • Open Access

Scalar leptoquark contributions to the gg→Zh process

Shi-Ping He*

  • *Contact author: heshiping@tyut.edu.cn
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Phys. Rev. D 113, 015039 – Published 28 January, 2026

DOI: https://doi.org/10.1103/23gr-yygx

Abstract

In this manuscript, we study the general scalar leptoquark contributions to the gg→Zh process at a one-loop level. We find that the contributions only show up for the off diagonal Higgs and Z boson interactions with scalar leptoquarks, which can lead to new tensor structures different from the standard model. In the one-field and two-field models, the contributions vanish exactly; thus, the contributions are possible at least in the three-field models. We exemplify the contributions in the S1+R˜2+S3 model, which can appear in the presence of scalar leptoquark mass splittings and CP violation. In view of the heavy scalar leptoquark mass suppression, the leading contributions are typically small and difficult to observe at hadron colliders. However, this work offers a quantitative and systematic investigation of scalar leptoquark contributions, also making it valuable for the new physics studies in other models.

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Phys. Rev. D 113, 015039– Published 28 January, 2026
  • Received 14 September 2025
  • Accepted 6 January 2026
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