Understand
Production of a single top quark provides excellent opportunity for understanding top quark physics and Cabibbo-Kobayashi-Maskawa structure of the quark sector in the Standard Model.
- Although an associated production with a b-quark has already been observed at the Tevatron in 2009, a single top production in association with a W gauge boson has not been observed till 2014 at the LHC, where pair production of the top quark serves as the dominant background.
- Due to the kinematic similarity between tW and the dominant background, it is challenging to find suitable kinematic variables that offer good signal-background separation, which naturally leads to the use of multivariate methods.
- In this paper, we investigate kinematic structure of tW+j channel using M_T2 and invariant mass variables, and find that tW +j production could well be separated from tt production with high purity at a low cost of statistics when utilizing these kinematic correlations.