Description
The T2K experiment is a long-baseline accelerator neutrino experiment aimed at precise measurement of neutrino oscillation parameters. The near detector upgrade of the T2K experiment involves the commissioning of SuperFGD, a super-fine-grained 3D scintillator cube detector. The new detector allows for unprecedented precision in event-by-event reconstruction of neutron kinematics enabled by clear time reconstruction of interaction vertices. Neutron energy currently constitutes the largest systematic uncertainty in the reconstruction of neutrino energies, thereby limiting the sensitivity to neutrino interaction cross-section and oscillation. For the first time, a Markov-Chain based detector calibration technique is applied to calibrate the timing information. The algorithm, which iteratively calculates the time-offset of all 55000 channels, is mathematically proven to work with any detectors with highly correlated geometry. After the calibration, the SuperFGD achieves sub-nanosecond level time resolution.