Torus (CLAS12 Detector)

The CLAS12 at Jefferson Lab includes a Torus magnet with a 3.6 T (Tesla) conducting field. It is based on six conducting coils arranged symmetrically around the beam line.

The coil operates at a temperature of 4.5 K because of a flow of supercritical liquid helium.

Requirements
The CLAS12 torus requires (from http://www.jlab.org/Hall-B/clas12-web/subsystems/magnets-intro.html):
 * uniform coverage of a large momentum and angle range, and symmetry around the beam axis,
 * an open structure that allows for long path lengths for charge and neutral particles resulting in good particle identification through precise time-of-flight measurements,
 * low background from electromagnetic processes to reach high luminosity.

Layout
The magnetic field of the torus is always tranverse to the particle trajectory, creating an ideal momentum resolution for charged particles.

Links/Sources
CLAS12 Superconducting Magnets: http://www.jlab.org/Hall-B/clas12-web/subsystems/magnets-intro.html