Light Higgs bosons in two-Higgs-doublet models

We explore the possibilities in two-Higgs-doublet models of type I and type II for Higgs states with mass below about 60 GeV, i.e. less than half of the similar to 125 GeV mass of the observed SM-like Higgs boson. We identify the latter as either the lighter or the heavier CP-even state, h or H, and employ scans of the two-Higgs-doublet model parameter space taking into account all relevant theoretical and experimental constraints, including the most up-to-date Higgs signal strength measurements. We find that, in both type I and type II models, such light Higgs states are phenomenologically viable and can lead to interesting signatures. Part of the relevant parameter space may be testable with the existing 8 TeV LHC data, e.g. by looking for direct production of the light state via gg fusion or b (b) over bar associated production using its tau(+)tau(-) and mu(+)mu(-) decays at low invariant mass.