Probing Higgs Sector CP Violation with Top Quarks at a Photon Linear Collider

Abstract

We investigate for two-Higgs doublet models with intrinsic CP violation in the scalar potential CP-nonconserving effects in unpolarized $\gamma \gamma \to t\bar{t}$ for a range of neutral Higgs boson masses which includes resonant $\phi$ production and the subsequent decay of $\phi \to t\bar{t}$. The importance of taking into account, even in the resonant case, the interference with the nonresonant background is shown. Further, we propose and calculate three asymmetries which efficiently trace CP-violating effects in $\gamma \gamma \to t\bar{t}$ using semileptonic $t\bar{t}$ decays.

Comments: 13 pages, plain TeX; 6 figures available upon request from arndb@axpwb.physik.rwth-aachen.de