Operational Experience and Characterization of a Superconducting Transverse Gradient Undulator for Compact Laser Wakefield Accelerator-Driven FEL

A 40-period superconducting transverse gradient undulator (TGU) has been designed and fabricated at Karlsruhe Institute of Technology (KIT). Combining a TGU with a Laser Wakefield Accelerator (LWFA) is a potential key for realizing an extremely compact Free Electron Lasers (FEL) radiation source, as the TGU scheme is a viable option to compensate the challenging properties of the LWFA electron beam in terms of beam divergence and energy spread. The superconducting TGU has been commissioned off-line, step by step reaching its final operational parameters. A specially designed set-up for mapping of the magnetic field in the TGU's extremely narrow gap has been installed, commissioned and employed for the magnetic characterization. In this contribution, we report on the operational experience of the TGU and on the magnetic characterization measurement.