Closing the Window on Light Charged Higgs Bosons in the NMSSM

In the Next-to-Minimal SuperSymmetric Model (NMSSM) the lightest CP-odd Higgs bosons (a1) can be very light. As a consequence, in addition to the standard charged Higgs boson (h+) decays considered in the MSSM for a light charged Higgs (m_h+ < m_t), the branching fraction for h+ to a1 W can be dominant. We investigate how this signal can be searched for in t tbar production at the Large Hadron Collider (LHC) in the case that m_a1 \gtrsim 2m_B with the a1 giving rise to a single b bbar-jet and discuss to what extent the LHC experiments are able to discover such a scenario with an integrated luminosity \sim 20 fb-1. We also discuss the implications of the possible Higgs-signal observed at the LHC.