The final turn of the J-PARC extracted proton beam is a
superconducting combined function magnet line. The combined function
magnets are dipole cable magnets, typical of cold mass collared magnets,
but have been designed to include a large component of quadrupole field.
This provides both bending and focussing of the proton beam prior to
target impact, where neutrinos will be produced.
The BNL Superconducting Magnet Division is using its direct wind
facility to produce superconducting corrector magnets to be used in
conjunction with the combined function magnets.
The first direct wind magnet set designed and fabricated is a
combined function magnet with an additional skew dipole. This magnet is
intended to be used within the cable collared combined function dipole
used for the extraction line. By design, the combined function corrector
is magnetically orthogonal to the main magnet, preventing large induced
voltages within the corrector when the main magnet quenches. This
corrector is complete, and is currently included within the first full
length test magnet at KEK.
Link to combined function magnet details
The second corrector style contains both a dipole and a skew dipole.
These coil sets are being made using the single wire conductor. These
magnets are to be located between the main combined function magnets.
Four of these units will be fabricated, the prototype coilset is being
wound.
Link to interconnect corrector magnet
For more information contact
John Escallier
