JACoW is a publisher in Geneva, Switzerland that publishes the proceedings of accelerator conferences held around the world by an international collaboration of editors.
TY - CONF AU - Konomi, T.K. AU - Adolphsen, C. AU - Gatzmaga, S. AU - Hartung, W. AU - Kelly, M.P. AU - Kim, S.H. AU - Lewellen, J.W. AU - Miller, S.J. AU - Morris, D.G. AU - Murcek, P. AU - Petersen, T.B. AU - Saito, K. AU - Smedley, J. AU - Taylor, A.T. AU - Xiang, R. AU - Xiao, L. AU - Xu, T. AU - Yin, Z.Y. ED - Saito, Kenji ED - Xu, Ting ED - Sakamoto, Naruhiko ED - Schaa, Volker R.W. ED - Thomas, Paul W. TI - Design and Tests of a Cathode Stalk for the LCLS-II-HE Low Emittance Injector SRF Gun J2 - Proc. of SRF2023, Grand Rapids, MI, USA, 25-30 June 2023 CY - Grand Rapids, MI, USA T2 - International Conference on RF Superconductivity T3 - 21 LA - english AB - A SRF gun can operate CW with a high gradient and ultra-low vacuum for high-quantum efficiency, low MTE photocathodes, useful features for delivery of high-brightness, high-repetition-rate beams. For these reasons, an SRF gun based photoinjector was chosen for a proposed Low Emittance Injector addition to the LCLS-II-HE facility, which will operate CW with bunch rates up to 1 MHz. For this injector, a prototype 185.7 MHz QWR gun is being developed in a collaborative effort among FRIB, HZDR, ANL and SLAC, with the goal of achieving a photocathode gradient of at least 30 MV/m. The photocathode is held by a coaxial fixture (cathode stalk) for thermal isolation from the cavity body. The system must allow for precise alignment of the photocathode, particle-free photocathode exchange, cryogenic (55-70 K) or warm (273-300 K) photocathode operating temperatures, and DC biasing to inhibit multipacting. A prototype cathode stalk has been built and bench tests are underway to validate the design. Measurements include RF power dissipation, DC bias hold-off, multipacting suppression and heat transfer effectiveness. This paper describes the cathode stalk design and the test results. PB - JACoW Publishing CP - Geneva, Switzerland SP - 589 EP - 592 KW - cathode KW - gun KW - SRF KW - emittance KW - operation DA - 2023/09 PY - 2023 SN - 2673-5504 SN - 978-3-95450-234-9 DO - doi:10.18429/JACoW-SRF2023-TUPTB069 UR - https://jacow.org/srf2023/papers/tuptb069.pdf ER -