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

Abstract 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 $$\gamma \gamma $$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mi>γ</mml:mi> <mml:mi>γ</mml:mi> </mml:mrow> </mml:math> mode. The exclusion bounds on the ALP-top quark coupling depending on the ALP mass $$m_a$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msub> <mml:mi>m</mml:mi> <mml:mi>a</mml:mi> </mml:msub> </mml:math> are given. The mass range 10 GeV–10 TeV is considered. We have obtained that for $$m_a = 10$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:msub> <mml:mi>m</mml:mi> <mml:mi>a</mml:mi> </mml:msub> <mml:mo>=</mml:mo> <mml:mn>10</mml:mn> </mml:mrow> </mml:math> GeV the ALP-top quark couplings are as small as 0.17 $$\hbox {TeV}^{-1}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mtext>TeV</mml:mtext> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> and 0.11 $$\hbox {TeV}^{-1}$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:msup> <mml:mtext>TeV</mml:mtext> <mml:mrow> <mml:mo>-</mml:mo> <mml:mn>1</mml:mn> </mml:mrow> </mml:msup> </mml:math> 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.