The new superconducting RF photoinjector at the ELBE linac

Most of the proposed electron accelerator projects for future free electron lasers, energy recovery linacs, or 4
^th
generation light sources require electron beams with an unprecedented combination of high-brightness, low emittance and high average current. For that reason existing electron injectors must be considerably improved or new injector concepts developed. One very promising approach represents the superconducting radio frequency photoinjector (SRF gun). This injector type combines the advantages of a conventional photoelectron injector with that of superconducting acceleration, i.e. the very low RF losses and simple continuous wave operation. A SRF gun was developed and installed at Forschungszentrum Dresden-Rossendorf for operation at the ELBE superconducting linear accelerator. In November 2007 the first beam was produced. First commissioning results have been collected. Besides an improvement of beam quality and parameter range the SRF gun serves as a test bench for further development, evaluation and optimization since it is the first injector of its type which is operating at an accelerator worldwide