  We study here the di-muon decay mode of a very light CP-odd Higgs boson of the NMSSM, a1, produced in association with a bottom-antibottom pair and find that, despite small event rates, a significant signal should be extractable from the SM background at the LHC with high luminosity. 
Muon Signals of Very Light CP-odd Higgs states of the NMSSM at the LHC