Ruben Carcagno
This striking red wall, in combination with scintillator paddles behind it (not seen in the photo), is known as the MINERvA veto wall. Located in the NuMI neutrino beamline 105 meters underground, the veto wall tags muons that come from neutrinos that interact in the rock upstream of the wall. The muons then pass through into the rest of the MINERvA detector (into the plane of the picture). Marking these particles as they enter the detector allows scientists to distinguish…