Modulated double-helix quadrupole magnets

• Published in: IEEE transactions on applied superconductivity Vol. 13; no. 2; pp. 1369 - 1372
• Main Authors: Meinke, R.B., Goodzeit, C.L., Ball, M.J.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01-06-2003; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Apertures; Applied sciences; Coils; Coils (windings); Conductors; Electrical engineering. Electrical power engineering; Electromagnets; Exact sciences and technology; Geometry; Linear particle accelerator; Magnetic modulators; Magnets; Manufacturing; Modulation; Quadrupoles; Solenoids; Superconducting coils; Superconducting magnets; Superconductivity; Systematic errors; Various equipment and components; Particle accelerator; Multipole field; Superconducting magnet; Solenoid; Spacer; Bias; System design; Accelerator magnets; superconducting quadrupoles; Machine windings
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2003.812674

We describe a new technology for superconducting quadrupole magnets especially for use in particle accelerators. The principle is based on the application of a sinusoidal modulation to the axial positions of the conductor windings in solenoids. The method can also be employed to produce higher-order multipole fields. Due to their solenoid-like geometry, these coils are significantly simpler to manufacture than standard (racetrack) cosine-2-theta coils and have significantly smaller systematic field errors without using any field-shaping spacers. When two complementary coil layers (with opposite current flow) are combined, the solenoid components of the fields are cancelled and the quadrupole or higher-order fields add. An example of such a design is described which generates a gradient of 130 T/m with systematic errors less than 10/sup -8/ at 67% of the aperture.