Test of the triple Higgs boson form factor in ${\mu }^{-}{\mu }^{+}\to HH$

We study the sensitivity of the process ${\mu }^{-}{\mu }^{+}\to HH$ to the $q^2$-dependence of the $HHH$ form factor, which can reflect the Higgs boson structure, especially in the case of compositeness. We compute the Born and 1 loop SM contribution to this process. We then show how the ${\mu }^{-}{\mu }^{+}\to HH$ polarized and unpolarized cross sections are modified by the presence of various types of anomalous contributions to the $HHH$ form factor, in particular Higgs constituents in the case of compositeness.