Searching supersymmetric leptonic partner at the CERN LHC

Motivated by the observed excess of the di-photon signal in Higgs searches, σγγ/σSM≃1.5, we argue that models with enhanced Γ(h→γγ) alone are the most favorable scenarios when the latest LHC/Tevatron results are all taken into account. We study the phenomenology of a supersymmetric scenario of light stau that predicts a 125 GeV SM-like Higgs boson with enhanced di-photon decay through light stau loops. Since it is extremely challenging to search the Drell-Yan stau pair at the LHC due to the small production rate, we focus on the parameter space with enhanced production of inclusive stau pairs, in particular, via bb¯ fusion or gaugino pairs. We study its phenomenology in both pure leptonic tau τℓ± channels and hadronic tau tagged τh channels. We find the same-sign dilepton from χ˜1±χ˜20→τℓ±τℓ±+X may significantly improve the discovery potential with even 7-8 TeV LHC of O(30fb−1) data. In the case of hadronic tau pair, we use the final state j+τhτh+E̸T to search and find that even with the most optimistic region of M2∼200-300GeV, it requires at least 50 fb−1 data of 14 TeV LHC to reach a significance of 3.5σ. Therefore, we conclude it is difficult to claim discovery only through hadronic tau based on the data by the 2012 shut-down. 5σ reach for our most optimistic region then requires 100 fb−1 data with 14 TeV running.