Speaker
Description
T2K is a long-baseline neutrino oscillation experiment. Its primary goals are to test CP symmetry in the lepton sector and precisely measure oscillation parameters, such as $\theta_{23}$ and $\Delta m_{32}^{2}$. The experiment's near detector complex ND280 was recently upgraded and now includes a new highly-segmented scintillator detector, SuperFGD.
We present a study of the ND280 near detector's potential to search for hypothetical millicharged particles (mCPs) produced in proton-nucleus collisions at J-PARC. The analysis focuses on the signature of a pair of recoil electrons, aligned with the target, resulting from mCP double-scattering.
The latest results incorporates a more detailed simulation of the target and the entire beamline compared to previous studies, providing an refined model for the expected mCP flux. Furthermore, the analysis provides more relevant estimates of the recoil electron detection efficiencies, based on a full simulation of the detector response. Based on these results, we present updated sensitivity regions for the mCP search.
