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arXiv · 2107.01123

Constraints on anomalous quartic gauge couplings via $Z\gamma jj$ production at the LHC

Abstract

In this paper, we investigate the contributions of anomalous quartic gauge couplings (aQGCs) to $Z\gamma jj$ production at the Large Hadron Collider (LHC) in the context of Standard Model effective theory (SMEFT). When energy scale is large, the validity of SMEFT becomes an important issue. To ensure the validity, the unitarity bound is applied in a model independent approach, which is found to have significant suppressive effects on the signals of $O_{M_i}$ operators. The kinematic and polarization features of the aQGC signals are also studied. The polarization effect is useful to highlight the signals of $O_{T_i}$ operators. The sensitivity estimates on dimension-8 operators with unitarity bounds at $\sqrt{s}=14$ TeV are obtained.

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Ji-Chong Yang, Yu-Chen Guo, Chong-Xing Yue, Qing Fu. 2021-07-02. Constraints on anomalous quartic gauge couplings via $Z\gamma jj$ production at the LHC. https://doi.org/10.1103/physrevd.104.035015

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