Side view schematic diagram of the P0D (Pi-Zero Detector) subdetector of the ND280 detector ( the T2K experiment off-axis near detector), showing the structure of the layers. The white, zig-zag, and blue strip regions represent the vertical scintillator bars, the horizontal scintillator bars, and the water bag regions, respectively. In this drawing, the beam direction (+Z) is to the right, the +Y direction is up, and +X direction is into the drawing.
T2K Collaboration
CC BY 4.0
<a rel="nofollow" class="external free" href="https://arxiv.org/abs/1908.10249">https://arxiv.org/abs/1908.10249</a>