Ramped Electron Bunch Experiment

Sextupoles

The sextupoles for the Neptune S-Bahn were designed using the magnetostatics code RADIA developed at ESRF. They are constructed of 1010 steel with copper windings and are designed to produce a sextupole field strength of 43.9 Tesla per square meter per ampere of current.

The sextupoles have a length of 5cm and inner pole-to-pole diameter of 4cm. The diagram below shows the vertical (y) component of the magnetic field along a horizontal line beginning at the geometrical center of the magnet. The quadratic shape is characteristic of the 2nd order sextupole field.

Sextupoles are used on the UCLA S-Bahn beamline to correct nonlinear chromatic effects. The following diagram shows the placement of these sextupoles.

For more details on the use of the sextupoles, visit the Background section.