Research (out-date)

Ultimate goal of my research is to discover new physics beyond the Standard Model (SM) where we can explore with the LHC data. To illuminate the evidence of the new physics, I have two approaches: the SM precision measurement to identify the deviation from the prediction and direct/indirect searches for the evidence of new physics.

Particular interests for the new physics are to discover new neutral gauge boson that carry out the new

symmetry and force, so-called Z'. The Z´ boson can be introduced from much wider theoretical models like non-abelian gauge group, extra dimensions (Kaluza-Klein excitation), dynamical symmetry breaking, grand unification theory etc. These interests are shared with Prof. Un-ki Yang's group and various approaches are performed by a SNU-CMS group (collaboration of Prof. Yang's and my groups) under the Korea CMS collaboration and BRL project.

I explore the searches in dilepton final state. The main background is Drell-Yan (DY) process decaying into dilepton and I lead international

collaboration team for the DY differential cross section measurements at the CMS experiment since 2010 to understand the dominant background better. The extension to the various channels (dilepton + X) for the Z' search is on-going at SNU.

• Keyword: CERN, LHC, CMS, Trigger, Muon, Standard Model, Quark, Lepton, Drell-Yan, Z boson, Higgs boson, Z', Cross Section, Beyond the Standard Model, Dark Matter, dark photon