Magnetic horns

How magnetic horns work

To make good neutrino beam with aligned direction, pions generated on the production target must be aligned as parallely as possible. It can be achieved by generating magnetic field with toroidal shape by the equipments called magnetic horns.

Magnetic horns are comprised of two coaxial barrels made of electrically conductive material. As shown in the following figure (K2K horns), the high electric current can generate magnetic field with toroidal shape (like a doughnut in front) only between the barrel-shaped conductors.