LHC τ -rich tests of lepton-specific 2HDM for (g − 2) μ

The lepton-sepcific (or type X) 2HDM (L2HDM) is an attractive new physics candidate explaining the muon g − 2 anomaly requiring a light CP-odd boson A and large tan β. This scenario leads to τ -rich signatures, such as 3τ , 4τ and 4τ + W/Z, which can be readily accessible at the LHC. We first study the whole L2HDM parameter space to identify allowed regions of extra Higgs boson masses as well as two couplings λ hAA and ξ which determine the 125 GeV Higgs boson decays h → τ + τ − and h → AA/AA ∗(τ + τ −), respectively. This motivates us to set up two regions of interest: (A) m A ≪ m H ∼ m H ± , and (B) m A ∼ m H ± ∼ O (100)GeV ≪ m H , for which derive the current constraints by adopting the chargino-neutralino search at the LHC8, and then analyze the LHC14 prospects by implementing τ -tagging algorithm. A correlated study of the upcoming precision determination of the 125 GeV Higgs boson decay properties as well as the observation of multi-tau events at the next runs of LHC will be able to shed light on the L2HDM option for the muon g − 2.