THA2WC —  WG-C   (08-Mar-18   11:00—12:30)
Chair: C.-J. Jing, Euclid TechLabs, LLC, Solon, Ohio, USA
Paper Title Page
Ultra-short Period High Field Undultators for Compact Light Sources  
  • T. Kii
    Kyoto University, Kyoto, Japan
  Funding: This work was supported by the Grant-in-Aid for Scientific Research (A), Japan Society for the Promotion of Science (17H01127)
Generation of strong periodic magnetic field in short period is important technology for future advanced light sources such as free electron lasers and synchrotron radiation facilities. However, the period length and K-value of undulators are limited by the maximum energy product of permanent magnet or engineering critical current density of superconducting wire in general. In order to overcome these technological limit, use of bulk superconductor has been proposed. The critical current densities of rare earth barium copper oxide (REBCO) exceeds 10 kA/mm2 at low temperature. This value is about 10 times higher than the engineering critical current density of superconducting wire. The maximum trapped magnetic field by REBCO bulk superconductor exceeds 17 T *,**. If this high density supercurrent are fully handled, ultra-short period high field undulator is realized. In this presentation, I will introduce several approaches of bulk superconductor undulators and summarize the merit and the drawback of them, then the potential of the bulk superconductors will be discussed.
* M. Tomita and M. Murakami, Nature 421 pp. 517'520, 2003
** J. H. Durrell et al., Supercond. Sci. Technol. 27 082001, 2014
slides icon Slides THA2WC01 [14.861 MB]  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
Generation of a Wakefield Undulator in Plasma With Transverse Density Gradient  
  • G. Stupakov
    SLAC, Menlo Park, California, USA
  Funding: This work was supported by the U.S. Department of Energy under contracts No. DE-AC02-76SF00515.
We show that a short relativistic electron beam propagating in a plasma with a density gradient perpendicular to the direction of motion generates a wakefield in which a witness bunch experiences a transverse force. A density gradient oscillating along the beam path would create a periodically varying force'an undulator, with an estimated strength of the equivalent magnetic field more than ten Tesla. This opens an avenue for creation of a high-strength, short-period undulators, which eventually may lead to all-plasma, free electron lasers where a plasma wakefield acceleration is naturally combined with a plasma undulator in a unifying, compact setup.
slides icon Slides THA2WC02 [4.470 MB]  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
A Beam-Driven Short Wavelength Undulator for FEL  
  • C.-J. Jing
    Euclid TechLabs, LLC, Solon, Ohio, USA
  The idea of the beam-driven accelerators where intense electron beams are used directly to drive electromagnetic fields that accelerate probe or 'witness' electron beams has been known as the wakefield acceleraion for decades. This technology presents significant possibilities to accelerate electron beams in a multiGeV scale in a compact footprint. Here we unveil the next logical step in the application of wakefields, using intense electron beams to create fields that directly guide and periodically deflect 'witness" electrons, causing them to radiate photons. This is a new application of wakefield principles that may be used in the near future to develop compact undulators. The combination of a compact accelerator and a compact undulator could lead to a very compact x-ray free-electron laser in the future.  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)