An example electron-neutrino event before and after applying the "charge-light" matching algorithm. A neutrino interaction is typically mixed with about 20 cosmic rays during the event recording of 4.8 milliseconds. After matching the neutrino interaction's "charge" signal, recorded by the wires, with its "light" signal, recorded by the photomultiplier tubes, it can be clearly singled out from the cosmic ray background. In the event display, the black points are from the electron-neutrino interaction and the colored points are the background cosmic rays. The size of each red circle shows the strength of the matched light signal for each photomultiplier tube.