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 - UNPB AU - Velthaus, V. AU - Bender, M. AU - Trautmann, C. ED - Herfurth, Frank ED - Schaa, Volker RW TI - Surface Treatment Procedures to Mitigate Ion-Induced Desorption in Heavy Ion Accelerators J2 - Proc. of HIAT2022, Darmstadt, Germany, 27 June-01 July 2022 CY - Darmstadt, Germany T2 - International Conference on Heavy Ion Accelerator Technology T3 - 15 LA - english AB - Ion-induced desorption is a serious limitation for stable operation of high beam intensities in heavy ion synchrotrons. Next generation heavy ion accelerators like FAIR or SPIRAL2 are designed for intensities that are orders of magnitude higher than the intensity of existing machines. Hence, ion-induced desorption becomes a big challenge. To better understand and control the influence of material and surface factors, desorption measurements with swift heavy ions (Ca and Au at 4.8 MeV/u) were conducted with focus on oxygen-free copper and tungsten samples. The surfaces were treated by different combinations of milling, lapping, polishing, etching and sputtering. Some of the samples were coated by carbon, titanium nitride or TiZrV. For all tested samples desorption yields (number of released molecules per impacting ion) for H₂, H₂O, CO, CO₂, O₂ and Ar will be presented. For copper, surface cleaning by sputtering with 5 keV argon ions reduces the desorption yield significantly. Another promising method to reduce ion-induced desorption is thermal annealing at 400 °C for about 4 h under ultra-high vacuum conditions. Suitable annealing and cleaning parameters will be presented. PB - JACoW Publishing CP - Geneva, Switzerland ER -