1. Field Emission onset data from VTA testing of C50 pairs
Liang Zhao
09/09/2016

2. How were data acquired Collect all data from traveler
Double check original data and compare with traveler
Definition of FE onset and value
First point rising above noise level on Radiation-Eacc curve
FE processed away are counted
FE towards/at quench are counted
Showing only final test result of qualified cavities
Horizontal axis is along cavity test sequence, equivalent to timeline
Emax is directly from traveler

3. Here FE onset at zero = no FE.
Year
2006
2007
2008
2009
2013
2014
2016
# of points 9 27 22 16 1 8
Summary of final test and qualified C50 cavities in VTA. Each point is a VTA test performed. Most of these cavities were build into pairs.
Here FE onset at zero = no FE.

4. # of pairs need VTA re-test # of VTA tests to qualify pair
VTA re-tests to qualify cavity pair
(preliminary analysis)
Year
# of pairs qualified
# of pairs need VTA re-test
# of VTA tests to qualify pair
2006 4
2.5
2,2,2
2007 16
2,2,2,3
2008 12
2,2,2,2
2009 8 2
3,2
2013
2016
2,2
1 CM = 4 pairs = 8 cavities