The main goal of NA62 experiment is to study extremely rare kaon decay $K^+\to \pi^+\nu\bar\nu$ with 10% precision. This decay is strongly supressed in Standard Model (SM) and could be calculated with high precision BR($K^+\to \pi^+\nu\bar\nu$) = $7.81\times 10^{−11}$ which makes it sensitive to New Physics beyond the Standard Model.
One of the important detectors of NA62 trigger system is Charged-particle Hodoscope (CHOD) — system of scintillation counters with pad structure covering area around the beam pipe. CHOD is designed to define the aperture for charged particles for the level-0 trigger and to veto possible interactions in the RICH mirror plane ($\approx$ 20% of radiation length). New CHOD is scintillating hodoscope with a pad structure and a total number of 148 counters. Each pad readout with WLS fibers and two or four SensL SiPM’s with a sensitive area of 3 $\times$ 3 mm2. This photosensor has 4774 pixels, each of 35$\times$35 $\mu$m$^2$. The main parameters (photon detection efficiency, dark rate, cross-talk, and gain) of 500 SiPM’s were measured. The results will be presented in the poster.

INR, MEPhI

INR, MEPhI, MIPT