Ghost Particle: Neutrino Detector (3D)

Neutrinos interact with matter so weakly that a detector needs enormous mass and years of exposure to catch a handful of real events — this is why physicists call them "ghost particles". This simulator renders a Super-Kamiokande-style cylindrical tank lined with photomultiplier tubes: a beam of neutrinos streams straight through the target almost every time, while the true exponential interaction law P = 1 − e^(−nσL) decides, crossing by crossing, whether a rare Cherenkov flash lights up the PMT wall. Detector size, target density, beam energy, flux and simulated exposure time all feed the same real formula used by working detectors to plan how big — and how patient — an experiment has to be.