It may couple to itself, that is.The Higgs boson is analogous to the gluon in this respect, but similarities end there. The reason is that one of the ways you can produce a pair of Higgs bosons in proton-proton collisions is by producing a Higgs boson with much more energy than its rest mass (a virtual Higgs boson, also called \"off mass shell\"). Below are some Feynman diagrams thatdescribe how those five parameters would affect Higgs pair production. This may happen if any one of five \"effective\" parameters has a value different from their Standard Model value. A small signal due to single Higgs boson production is certainly present there, although the special selection (that requires the presence of another Higgs decay candidate to b-quark jets) does not allow it to be visible.