Higgs probes of top quark contact interactions and their interplay with the Higgs self-coupling

We calculate the dominant contributions of third generation four-quark operators to single-Higgs production and decay. They enter via loop corrections Higgs decays into gluons, photons $b\bar{b}$, in gluon fusion association with top quark pairs. show that these effects can, some cases, lead better constraints than those from fits data. Finally, we investigate whether four-fermion can spoil determination trilinear self-coupling