High gradient performances of bulk niobium cavities go through a low-temperature baking during one or two days, the temperature parameter is adjusted in a narrow tuning range around 110 or 120 °C. With such treatment, the intrinsic quality factor Q0 is improved at high fields.
Assuming the oxygen diffusion is involved in this phenomenon, we have developed the “Fast-Baking” (145 °C / 3 hours) as an alternative method. Similar results have been achieved with this method compared to standard baking. Consequently, for the first time, a link between oxygen diffusion and high field Q-slope has been proved.
Furthermore this method open the way to a simpler and better baking procedure for the large-scale cavity production due to:
- the baking time reduction and
- the possibility to combine baking and drying during cavity preparation.
|
