Development of a Superconducting Transverse-Gradient Undulator for Laser-Wakefield Accelerators

• Published in: IEEE transactions on applied superconductivity Vol. 23; no. 3; p. 4101505
• Main Authors: Rodriguez, Verónica Afonso, Bernhard, A., Keilmann, A., Peiffer, P., Rossmanith, R., Widmann, C., Baumbach, T., Nicolai, M., Kaluza, M. C.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: New York, NY IEEE 01.06.2013; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Accelerators; Applied sciences; Beams (radiation); Coils; Electrical engineering. Electrical power engineering; Electromagnets; Electron beams; Errors; Exact sciences and technology; Finite element methods; Free electron lasers; Laser beams; Monochromatic radiation; plasma accelerators; Spectra; Spreads; superconducting coils; Superconducting magnets; Superconductivity; synchrotron radiation; Syntax; Undulators; Various equipment and components; Windings; High intensity; undulators; Performance characteristic; plasma accelerators; Electron beam; Relativistic electron; Monochromatic radiation; Finite element methods; Cylindrical shape; Superconducting coils; Optimal design; Finite element method; Electron accelerators; Synchrotron radiation
• ISSN: 1051-8223; 1558-2515
• DOI: 10.1109/TASC.2013.2240151

Relativistic electrons with small energy spread propagating through undulators produce monochromatic radiation with high spectral intensity. The working principle of undulators requires a small energy spread of the electron beam in the order of Δ E / E ~ 0.1%. Laser-wakefield accelerators can produce electron bunches with an energy of several 100 MeV within a few millimeters acceleration length, but with a relatively large energy spread (Δ E / E ~ 1-10%). In order to produce monochromatic undulator radiation with these electrons, a novel scheme involving transverse-gradient superconducting undulators was proposed in an earlier work. This paper reports on the design-optimization and construction of an iron-free cylindrical superconducting undulator tailored to the particular beam properties of the laser-wakefield electron accelerator at the University of Jena, Germany.