Observability of γγ decays of Higgs bosons from supersymmetry at hadron supercolliders

Motivated by the recent discovery that radiative corrections can cause the mass of the lightest scalar Higgs boson ${\mathit{H}}_{\mathit{l}}$ of the minimal supersymmetric model (MSSM) to be in the intermediate-mass range, we assess the prospects for discovering the MSSM Higgs bosons via their γγ decay modes at the Superconducting Super Collider (SSC) and at the CERN Large Hadron Collider (LHC). We find that if the charged Higgs boson is not too light, it is possible to discover at least one of the Higgs bosons via this mode within a few years of operation of the SSC, provided the detector has the resolution to identify a standard model Higgs boson in the intermediate-mass range via its γγ decay. Similar conclusions hold at the LHC provided the luminosity is higher by a factor of about 4. In the case where ${\mathit{m}}_{\mathit{H}}^{+}$, and hence ${\mathit{m}}_{\mathit{H}\mathit{p}}$, is somewhat smaller than 200 GeV, we find there are regions of parameter space where all three Higgs bosons are in the intermediate-mass range, and none of them lead to an observable signal. Thus, new strategies may be needed to identify the Higgs bosons of the MSSM.