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 - Peacock, R.C. AU - Bellodi, G. AU - Burt, G. AU - Calatroni, S. AU - Da Palma Serafim, C.F. AU - Grudiev, A. AU - Lombardi, A.M. AU - Perez Fontenla, A.T. AU - Ramberger, S. AU - Sargsyan, E. AU - Sgobba, S. AU - Wuensch, W. ED - McIntosh, Peter ED - Burt, Graeme ED - Apsimon, Robert ED - Schaa, Volker R.W. TI - Pulsed DC High Field Measurements of Irradiated and Non-Irradiated Electrodes of Different Materials J2 - Proc. of LINAC2022, Liverpool, UK, 28 August-02 September 2022 CY - Liverpool, UK T2 - International Linear Accelerator Conference T3 - 31 LA - english AB - Beam loss occurs in Radio Frequency Quadrupoles (RFQ), and has been observed in the H⁻ linear accelerator Linac4 (L4) at CERN. To determine if beam loss can induce breakdowns, and to compare the robustness of different materials, tests have been done using pulsed high-voltage DC systems. Electrical breakdown phenomena and conditioning processes have been studied using these systems. Cathodes of different materials were irradiated with 1.2x10¹⁹ H⁻ p/cm², the estimated beam loss of the L4 RFQ over 10 days. The irradiated electrodes were installed in a system to observe if the irradiated area coincided with the breakdown locations, with pulsing parameters similar to the RFQ. Tests of irradiated and non-irradiated electrodes of the same material were done for comparison. The main difference observed was an increase in the number of breakdowns during the initial conditioning that returned to non-irradiated sample values with further running. Visual observations after irradiation show the beam centre and a halo the same diameter of the beam pipe. Breakdown clusters occur in the centre and halo regions, suggesting irradiation is not the only factor determining the breakdown probability. PB - JACoW Publishing CP - Geneva, Switzerland SP - 441 EP - 444 KW - radiation KW - rfq KW - cathode KW - vacuum KW - linac DA - 2022/09 PY - 2022 SN - 2226-0366 SN - 978-3-95450-215-8 DO - doi:10.18429/JACoW-LINAC2022-TUPOPA13 UR - https://jacow.org/linac2022/papers/tupopa13.pdf ER -