Search for Higgs boson decays into a pair of light bosons in the bb mu mu final state in pp collision at root s=13 TeV with the ATLAS detector
A search for decays of the Higgs boson into a pair of new spin-zero particles, H -> aa, where the a-bosons decay into a b-quark pair and a muon pair, is presented. The search uses 36.1 fb(-1) of proton-proton collision data at root s = 13 TeV recorded by the ATLAS experiment at the LHC in 2015 and 2016. No significant deviation from the Standard Model prediction is observed. Upper limits at 95% confidence level are placed on the branching ratio (sigma(H)/sigma(SM)) x B(H -> aa -> bb mu mu), ranging from 1.2 x 10(-4) to 8.4 x 10(-4) in the a-boson mass range of 20-60 GeV.