Charge asymmetry in $\bm{\gamma\gamma \to \mu^+\mu^- + neutrinos}$ with   polarized photons
  The difference in distributions of $\mu^+$ and $\mu^-$ in reactions $\gamma \gamma \to \mu^+\mu^-+\nu\bar\nu$ and $\gamma \gamma \to W^\pm\mu^\mp +\nu(\bar\nu)$ with polarized photons at $\sqrt{s}>200$ GeV is a large observable effect which is sensitive to New Physics phenomena. 
D. A. Anipko, M.Cannoni, I. F. Ginzburg, A. V. Pak, O. Panella