Searching for a very light Higgs boson at the Tevatron

Abstract

Light Higgs bosons (h^0) with a mass below 60 GeV may have escaped detection at LEP due to a suppressed cross-section for e^+e^-\to Zh^0. Their discovery is also problematic in standard search channels at the Tevatron Run II and LHC. Such a h^0 can arise in the two Higgs doublet model (2HDM) and in the Minimal Supersymmetric Standard Model (MSSM) with explicit CP violating phases. We propose the mechanism p\bar p \to H^\pm h^0 which offers cross-sections of up to 500 fb in the 2HDM, or up to 100 fb in the MSSM. The possibility of a large branching ratio for H^\pm\to h^0W^\pm would give rise to the non-standard signature h^0h^0W^\pm which might facilitate detection.