Selection of multi-ring charged current vu 1π+ samples at T2K far detector

Tokai to Kamioka (T2K) is an accelerator long baseline experiment that measures the neutrino oscillation parameters by observing $nu_mu$ ($bar{nu}_mu$) disappearance and $nu_e$ ($bar{nu}_e$) appearance from a nearly pure $nu_mu$($bar{nu}_mu$) beam. The experiment has both near and far detectors situated at 280 m and 295 km respectively from the beam production target. The far detector Super-Kamiokande (SK) where $nu$ and $bar{nu}$ interact is a water Cherenkov detector. The dominant interactions at $sim0.6$ GeV where T2K flux peaks are charged current quasi--elastic (CCQE) which result in single ring events. The next largest CC interaction at T2K energy is resonant 1$pi$ production where the events will have multi--ring topology. The addition of CC $nu_mu1pi^+$ samples to the T2K analysis is expected to improve the precision on $sin^2theta_{23}$ and $|Delta{m^2_{32}}|$. A cut based selection study is used to select $nu_mu$CC $1pi^+$ like events accumulated in neutrino enhanced beam operation. The details of this study will be presented in this poster.