Magnetic Elements for the A1900 Fragment Separator at the NSCL

Prototype of the Superferric Dipoles for the Super-FRS of the FAIR-Project

“…In matters of design, size, field, weight and stored energy the CR/Super-FRS dipole is very similar to the superconducting dipoles of the A1900 fragment separator of the National Superconducting Cyclotron Laboratory at Michigan State University (NSCL, MSU) [6].…”

A superferric quadrupole for use in an SRF cryomodule

“…The dimensions and gradient requirements are given in Table I. The ratio of the length-to-diameter is identical to that of the largest bore magnet used in the NSCL's recent A1900 upgrade [4]. The physical length of the quad was determined by scaling the A1900 quad to the required 50 mm effective length.…”

“…The required quadrupole gradient can be reached both by normal conducting and superconducting magnets. Superferric quadrupoles [4], combining a very compact size with a low power dissipation in the cryostat, have been found to be an excellent solution for this linac. A potential drawback is the residual magnetic field of the iron core, which must be shielded below 1 µ T during cavity cooldown to prevent performance degradation of the nearby superconducting cavities.…”

Conceptual Design of Cryogenic Facilities for Super-FRS of FAIR

“…All magnets in the multiplet cryostat are cooled with liquid helium in a common helium bath. The same principle is used for the A1900 quadrupole triplet [2] and the quadrupole triplet for the BigRIPS at RIKEN, Japan [3]. The overall cryogenic distribution for the superconducting magnets of the Super-FRS has been discussed in [4].…”

“…Each dipole stage consists of 3 dipole units which have the bending angles of 11 (pre-separator) and 9.75 (main-separator) respectively. Super-ferric dipoles of similar design are installed in the A1900 Fragment-Separator at MSU [2]. Each dipole stage is equipped with two multiplets, one before and one behind the dipole stage.…”