Search for invisible dark photon in γe\gamma e scattering at future lepton colliders

For the first time, the production of a massive dark photon (DP) in the $\gamma e^-$ scattering at the future lepton colliders ILC, CLIC, and CEPC is examined. The invisible decay mode of the DP is addressed. We have studied both the unpolarized scattering and the collision of the Compton backscattered photons with the polarized electron. The missing energy distributions are shown. We have considered the wide range 10 GeV -- 1000 GeV of the DP mass $m_{A'}$. The excluded regions at the 95\% C.L. in the plane $(\varepsilon, m_{A'})$, where $\varepsilon$ is the kinetic mixing parameter, are obtained.Comment: 24 pages, 10 figures; one equation and two references are adde

Search for the RS model with a small curvature through photon-induced process at the LHC

In this paper, potential of the LHC to explore the phenomenology of the Randall-Sundrum-like scenario with the small curvature for the process $pp \to p \gamma \gamma p \to p \mu^- \mu^+p$ through the subprocess $\gamma \gamma \to \mu^- \mu^+$ is examined for two forward detector acceptances, $0.0015 < \xi< 0.5$ and $0.1< \xi <0.5$. This process is known to be one of the most clean channels. The sensitivity bounds on the anomalous model parameters have been found at the $95\%$ confidence level for various LHC integrated luminosity values.Comment: 22 pages, 8 figures; 11 equations and 8 references are adde

Probing anomalous γγγγ\gamma\gamma\gamma\gamma couplings at a future muon collider

We have studied anomalous four-photon couplings in the $\mu^+\mu^- \rightarrow \mu^+ \gamma\gamma \mu^-$ scattering at a future muon collider, assuming that anomalous quartic gauge couplings with one or two $Z$ bosons are zero. The collision energies of 3 TeV, 14 TeV, and 100 TeV are addressed. Both differential and total cross sections versus invariant mass of the outgoing photons are calculated. The best 95\% C.L. exclusion bounds on anomalous couplings are obtained to be $g_1 = 2.23 \times 10^{-8}$ TeV$^{-4}$ and $g_2 = 4.22 \times 10^{-8}$ TeV$^{-4}$. They correspond to the muon collision energy of 100 TeV. The partial-wave unitary constraints on $g_1$ and $g_2$ are examined. We have demonstrated that the unitarity is not violated in a region of the anomalous couplings obtained in the present paper.Comment: 24 pages, 6 figure