Nuclear Physics Meets Neutrinos

Neutrino beams, such as those currently operating at Fermilab in the USA and J-PARC in Japan, are typically produced by colliding high-energy proton beams with long, thin solid targets. These collisions result in a spray of particles including short-lived hadrons such as pions or kaons. The hadrons are focused using magnetic focusing horns, which direct the hadrons into long tunnels, where they decay to neutrinos. Thick volumes of rock and shielding stop all particles except neutrinos, creating a beam of neutrinos.