Analysis of axion-like particles in a top-quark pair production at the CLIC

We examine a contribution of axion-like particles (ALPs) to a top pair production via the collision of Compton backscattered photons at the CLIC operating in a $\gamma \gamma$ mode. The exclusion bounds on the ALP-top quark coupling depending on the ALP mass $m_a$ are given. The mass range 10 GeV – 10 TeV is considered. We have obtained that for $m_a=10$ GeV the ALP-top quark couplings as small as $0.17$ TeV${}^{-1}$ and $0.11$ TeV${}^{-1}$ can be probed at the CLIC with the energy of 1.5 TeV and 3 TeV, respectively. A comparison with other constraints on the ALP-top coupling is given.