How to Detect `Decoupled' Heavy Supersymmetric Higgs Bosons

Heretofore neglected decay modes of heavy MSSM Higgs bosons into a variety of neutralino pairs may push the LHC discovery reach for these crucial elements of an extended Higgs sector to nearly the TeV-scale – if sparticle-sector MSSM input parameters are favorable. This is well into the so-called decoupling region, including moderate to low tan(beta) values, where no known signals exist for said heavy Higgs bosons via decays involving solely SM daughter particles, and the lighter h^0 mimics the lone SM Higgs boson. While the expanse of the Higgs to sparticle discovery region is sensitive to a number of MSSM parameters, including in particular those for the sleptons, its presence is primarily linked to the gaugino inputs – in fact, to just one parameter, M_2, if gaugino unification is invoked. Thus consideration of high vs. low M_2 realms in the MSSM should be placed on a par with the extensive consideration already given to high vs. low tan(beta) regimes.