Heavy Higgs bosons at the LHC upgrade

We evaluate the discovery potential for the heavy Higgs bosons at the LHC energy upgrade with root s = 27 TeV. We assume the degenerate mass spectrum and an approximate alignment limit in the Type-II Two Higgs Doublet Model for illustration. We explore the observability of the heavy neutral Higgs bosons by examining the clean signals from H-0 -> W+W-, ZZ via gluon-gluon fusion production. The associated production of a top quark and a charged Higgs boson via gb -> tH(+/-) is adopted to predict the discovery potential of heavy charged Higgses. We also emphasize the potential importance of the electroweak production of Higgs boson pairs, i.e. pp -> W--/+ -> H(+/-)A(0) and pp -> Z*/gamma* -> H+H-. These are only governed by pure electroweak gauge couplings and can provide complementary information to the conventional signals in the determination of the nature of the Higgs sector.