Model-independent study on the anomalous $ZZ\gamma$ and $Z\gamma \gamma$ couplings at the future muon collider

Abstract

In this study, we investigate the potential of $\mu ^{-} \mu ^{+}\rightarrow Z\gamma \rightarrow \nu \bar{\nu }\gamma$ process at the future muon collider with a center-of-mass energy of 3 TeV to examine the anomalous ZZ$\gamma$ and $Z\gamma \gamma$ neutral triple gauge couplings defining CP-conserving $C_{\widetilde{B}W}/{\Lambda ^4}$ coupling and three CP-violating $C_{\mathrm{BB}}/{\Lambda ^4}$, $C_{\mathrm{BW}}/{\Lambda ^4}$, $C_{\mathrm{WW}}/{\Lambda ^4}$ couplings. All signal and relevant background events are generated in MadGraph and passed through Pythia for parton showering and hadronization. Detector effects are also considered via tuned muon detector cards in Delphes. The effects of systematic uncertainties of $0\%$, $3\%$ and $5\%$ on the sensitivities are studied. The best sensitivities obtained from the process $\mu ^{-} \mu ^{+}\rightarrow Z\gamma \rightarrow \nu \bar{\nu }\gamma$ are $[-6.53;6.64]\times 10^{-2}$ TeV$^{-4}$ on CP-conserving $C_{\widetilde{B}W}/{\Lambda ^4}$ coupling and $[-2.47;2.47]\times 10^{-2}$ TeV$^{-4}$, $[-8.46;8.46]\times 10^{-2}$ TeV$^{-4}$ and $[-2.20;2.20]\times 10^{-1}$ TeV$^{-4}$ on CP-conserving $C_{\mathrm{BB}}/{\Lambda ^4}$, $C_{\mathrm{BW}}/{\Lambda ^4}$, $C_{\mathrm{WW}}/{\Lambda ^4}$ couplings , respectively. Our obtained results on the anomalous neutral gauge couplings set more stringent sensitivity, ranging between 5 and 15 times than the current experimental results while slightly better than the phenomenological studies at future pp colliders such as the HL-LHC, the HE-LHC and the FCC-hh, respectively. On the other hand, we can see that the bounds on the anomalous neutral gauge couplings expected to be obtained for the future $e^{-}e^{+}$ colliders such as the CLIC are roughly 2 times better than our results.