High gradients, on bulk niobium cavities, can only be reached after an imperative baking at low temperature to suppress the high field Q-drop.
We demonstrate in this paper that the commonly used standard process (under ultra high vacuum at 120°C for 48 hours) could be now simplified in terms of duration (3 hours at 145°C) and requirement (argon atmosphere instead of vacuum). Some efforts to more reduce duration, down to only one hour, have been undertaken to validate hypothesis and understand baking phenomenon. The next improvement step with the open-ended treatment of cavities in oxygen free atmosphere is underway and it does not seem hard to achieve. This new “fast baking” procedure will be very useful in the XFEL and ILC projects where Nb cavities mass production is required.
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