Search for Higgs boson decays into a pair of light bosons in the $bb\mu\mu$ final state in $pp$ collision at $\sqrt{s} = $13 TeV with the ATLAS detector

Understand

A search for decays of the Higgs boson into a pair of new spin-zero particles, $H \to aa$, where the $a$-bosons decay into a $b$-quark pair and muon pair, is presented.

• The search uses 36.1 fb$^{-1}$ of proton-proton collision data at $\sqrt{s}=13$ 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 $(\sigma_H / \sigma_{SM}) \times B(H\to aa\to bb\mu\mu)$, ranging from $2\times 10^{-4}$ to $10^{-3}$ in the $a$-boson mass range of 20-60 GeV.