The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Wenskat, M. AU - Bate, C. AU - Butterling, M. AU - Cizek, J. AU - Hirschmann, E. AU - Liedke, M.O. AU - Reschke, D. AU - Wagner, A. AU - Weise, H. ED - Michel, Peter ED - Arnold, André ED - Schaa, Volker RW TI - Vacancy-Hydrogen Dynamics in Samples During Low Temperature Baking J2 - Proc. of SRF2019, Dresden, Germany, 30 June-05 July 2019 CY - Dresden, Germany T2 - International Conference on RF Superconductivity T3 - 19 LA - english AB - The recent discovery of a modified low temperature baking process lead to a reduction of surface losses and an increase of the accelerating gradient of TESLA shape cavities. The hypothesis linking the accelerator performance and the treatment is the suppression of lossy nanohydrides via defect trapping, with vacancy-hydrogen complexes forming at the lower temperatures. Utilizing Doppler broadening Positron Annihilation Spectroscopy and Positron Annihilation Lifetime Spectroscopy samples made from European XFEL niobium sheets and cavity cut-outs were investigated. The evolution of vacancies, hydrogen and their interaction at different temperature levels have been studied during in-situ annealing. Measurements of niobium samples and a correlation between RF, material properties, and V-H distribution in cavity cut-outs has been done. PB - JACoW Publishing CP - Geneva, Switzerland SP - 83 EP - 86 KW - positron KW - niobium KW - cavity KW - lattice KW - electron DA - 2019/08 PY - 2019 SN - "" SN - 978-3-95450-211-0 DO - doi:10.18429/JACoW-SRF2019-MOP024 UR - http://jacow.org/srf2019/papers/mop024.pdf ER -