View source for Reza's thoughts on bunchlength measurement at UITF

Checking the bunch length system with 200keV beam and No choppers

Requirements: At minimum we need the following
#-	Beam through bunch length cavity
#-	More than 5uA tune beam
#-	200 keV  energy or higher
#-	Bunch length less than 30 degree of 1497 (typical low current beam at the gun)

Procedure: 
#)	With choppers and buncher off, thread the 200 keV beam from gun up through the bunch length cavity. 
#)	Setup more than 5uA tune beam (preferably to a beam dump or Fcup).
#)	Check the bunch length system by answering the following questions
#)	Do you see the bunch length output signal? If not stop and investigate.
#)	Does the bunch length signal change as the gun laser phase changes (multiples of 5 degrees, up to +/- 50 deg)? If not stop and investigate. Does the amount of change make sense?
#)	Does the bunch length signal changes as the 6 GHz reference signal phase is change (+/- 180 deg)? If not investigate.
#)	When all questions above have positive answer, the test is complete and system is checked for hardware.