Electromagnetic Investigation on a Sextupole HTS Magnet for RAON

The rare isotope accelerator complex for online experiments (RAON) is a heavy-ion accelerator equipped with an in-flight fragment separator (IF) system and isotope separation online technique in South Korea. Six quadrupole and a sextupole high-temperature superconducting (HTS) magnets are installed in the hot cell of the IF system, which is a high radiation region, to arrange the ion beams and correct the chromatic aberrations of the ion beams. The magnets are developed and installed for RAON at the Institute for Basic Science (IBS), South Korea. Superconducting magnet systems should be capable of a stable operation against high radiation heating and thermally and electromagnetically robust in the intense radioactive hot cell region. In this paper, we describe the design, fabrication, and evaluation of a sextupole HTS magnet. Electromagnetic designs are conducted considering the position of the HTS magnets and the angle of the yoke pole tip
et al.
The required design specifications are proposed as a part of RAON of IBS considering the following electromagnetic performance: 1) a magnetic field gradient of
$ \geq $
3.9 T/m
²
, 2) magnetic field uniformity of
$ < $
0.5%, 3) effective length of 450 ± 1 mm, and 4) operating temperature of ∼ 45 K.