Sextupole magnet

Sextupole electromagnet as used within the storage ring of the Australian Synchrotron to correct chromatic aberrations of the electron beam
Field lines of an idealized sextupole magnet in the plane transverse to the beam direction

A sextupole magnet (also known as a hexapole magnet) consist of six magnetic poles set out in an arrangement of alternating north and south poles arranged around an axis.[1] They are used in particle accelerators[1] for the control of chromatic aberrations and for damping the head—tail transverse plasma instability. Two sets of sextupole magnets are used in transmission electron microscopes to correct for spherical aberration.

The design of sextupoles using electromagnets generally involves six steel pole tips of alternating polarity. The steel is magnetised by a large electric current that flows in the coils of wire wrapped around the poles. The coils may be formed from hollow copper magnet wire that carry coolant, usually de-ionized water. The current density of such a conductor can be above 10 amps/mm2 (four times that of standard copper conductors).

  1. ^ a b "Sextupole magnet". The European X-Ray Laser Project (XFEL). n.d. Retrieved 2008-09-17.